Features/categories

96 files changed, 1904 insertions, 695 deletions

diff --git a/src/client/elm/Dialog.elm b/src/client/elm/Dialog.elm
index 3b9e93b..a7e059a 100644
--- a/src/client/elm/Dialog.elm
+++ b/src/client/elm/Dialog.elm
@@ -65,8 +65,7 @@ update updateModel msg baseModel model =
 
     UpdateAndClose msg ->
       ( { model | config = Nothing }
-      , Task.succeed ()
-          |> Task.perform (always msg) (always msg)
+      , Task.perform (always msg) (Task.succeed msg)
       )
 
     OpenWithUpdate config modelMsg ->
diff --git a/src/client/elm/Dialog/AddCategory/Model.elm b/src/client/elm/Dialog/AddCategory/Model.elm
new file mode 100644
index 0000000..8aeec1a
--- /dev/null
+++ b/src/client/elm/Dialog/AddCategory/Model.elm
@@ -0,0 +1,53 @@
+module Dialog.AddCategory.Model exposing
+  ( Model
+  , init
+  , initialAdd
+  , initialClone
+  , initialEdit
+  , validation
+  )
+
+import Date exposing (Date)
+import View.Date as Date
+
+import Form exposing (Form)
+import Form.Field as Field exposing (Field)
+import Form.Validate as Validate exposing (Validation)
+import Validation
+
+import Model.Translations exposing (Translations)
+import Model.Category exposing (Category, CategoryId)
+
+type alias Model =
+  { id : Maybe CategoryId
+  , name : String
+  , color : String
+  }
+
+init : Form String Model
+init = Form.initial [] validation
+
+initialAdd : Translations -> List (String, Field)
+initialAdd translations =
+  [ ("color", Field.string "#000000")
+  ]
+
+initialClone : Translations -> Category -> List (String, Field)
+initialClone translations category =
+  [ ("name", Field.string category.name)
+  , ("color", Field.string category.color)
+  ]
+
+initialEdit : Translations -> CategoryId -> Category -> List (String, Field)
+initialEdit translations categoryId category =
+  [ ("id", Field.string (toString categoryId))
+  , ("name", Field.string category.name)
+  , ("color", Field.string category.color)
+  ]
+
+validation : Validation String Model
+validation =
+  Validate.map3 Model
+    (Validate.field "id" (Validate.maybe Validate.int))
+    (Validate.field "name" (Validate.string |> Validate.andThen Validate.nonEmpty))
+    (Validate.field "color" (Validate.string |> Validate.andThen Validate.nonEmpty))
diff --git a/src/client/elm/Dialog/AddCategory/View.elm b/src/client/elm/Dialog/AddCategory/View.elm
new file mode 100644
index 0000000..6c02351
--- /dev/null
+++ b/src/client/elm/Dialog/AddCategory/View.elm
@@ -0,0 +1,72 @@
+module Dialog.AddCategory.View exposing
+  ( button
+  )
+
+import Html exposing (..)
+import Html.Attributes exposing (..)
+import Html.Events exposing (..)
+import Task
+
+import Form exposing (Form)
+import Form.Field as Field exposing (Field)
+import Utils.Form as Form
+
+import Dialog
+import Dialog.AddCategory.Model as AddCategory
+import Dialog.Msg as DialogMsg
+
+import Tooltip
+
+import View.Form as Form
+import View.Events exposing (onSubmitPrevDefault)
+
+import Msg exposing (Msg)
+import LoggedIn.Msg as LoggedInMsg
+import LoggedIn.Home.Msg as HomeMsg
+
+import Model.Translations exposing (getMessage)
+import Model.View exposing (View(LoggedInView))
+
+import LoggedData exposing (LoggedData)
+import LoggedIn.Home.Model as HomeModel
+
+button : LoggedData -> List (String, Field) -> String -> Html Msg -> Maybe String -> Html Msg
+button loggedData initialForm title buttonContent tooltip =
+  let dialogConfig =
+        { className = "categoryDialog"
+        , title = getMessage loggedData.translations title
+        , body = \model -> addCategoryForm loggedData model.addCategory
+        , confirm = getMessage loggedData.translations "Confirm"
+        , confirmMsg = submitForm << .addCategory
+        , undo = getMessage loggedData.translations "Undo"
+        }
+  in  Html.button
+        (  ( case tooltip of
+               Just message -> Tooltip.show Msg.Tooltip message
+               Nothing -> []
+           )
+        ++ [ onClick (Msg.Dialog <| Dialog.OpenWithUpdate dialogConfig (DialogMsg.Init "categoryname" (DialogMsg.AddCategoryMsg <| Form.Reset initialForm))) ]
+         )
+        [ buttonContent ]
+
+addCategoryForm : LoggedData -> Form String AddCategory.Model -> Html Msg
+addCategoryForm loggedData addCategory =
+  let htmlMap = Html.map (Msg.Dialog << Dialog.Update << DialogMsg.AddCategoryMsg)
+  in  Html.form
+        [ onSubmitPrevDefault Msg.NoOp ]
+        [ htmlMap <| Form.textInput loggedData.translations addCategory "category" "name"
+        , htmlMap <| Form.colorInput loggedData.translations addCategory "category" "color"
+        , Form.hiddenSubmit (submitForm addCategory)
+        ]
+
+submitForm : Form String AddCategory.Model -> Msg
+submitForm addCategory =
+  case Form.getOutput addCategory of
+    Just data ->
+      case data.id of
+        Just categoryId ->
+          Msg.Dialog <| Dialog.UpdateAndClose <| Msg.EditCategory categoryId data.name data.color
+        Nothing ->
+          Msg.Dialog <| Dialog.UpdateAndClose <| Msg.CreateCategory data.name data.color
+    Nothing ->
+      Msg.Dialog <| Dialog.Update <| DialogMsg.AddCategoryMsg <| Form.Submit
diff --git a/src/client/elm/Dialog/AddIncome/Model.elm b/src/client/elm/Dialog/AddIncome/Model.elm
index 0d52b22..ad7b25a 100644
--- a/src/client/elm/Dialog/AddIncome/Model.elm
+++ b/src/client/elm/Dialog/AddIncome/Model.elm
@@ -4,6 +4,7 @@ module Dialog.AddIncome.Model exposing
   , initialAdd
   , initialClone
   , initialEdit
+  , validation
   )
 
 import Date exposing (Date)
@@ -24,29 +25,29 @@ type alias Model =
   }
 
 init : Form String Model
-init = Form.initial [] validate
+init = Form.initial [] validation
 
 initialAdd : Translations -> Date -> List (String, Field)
 initialAdd translations date =
-  [ ("date", Field.Text (Date.shortView date translations))
+  [ ("date", Field.string (Date.shortView date translations))
   ]
 
 initialClone : Translations -> Date -> Income -> List (String, Field)
 initialClone translations date income =
-  [ ("amount", Field.Text (toString income.amount))
-  , ("date", Field.Text (Date.shortView date translations))
+  [ ("amount", Field.string (toString income.amount))
+  , ("date", Field.string (Date.shortView date translations))
   ]
 
 initialEdit : Translations -> IncomeId -> Income -> List (String, Field)
 initialEdit translations incomeId income =
-  [ ("id", Field.Text (toString incomeId))
-  , ("amount", Field.Text (toString income.amount))
-  , ("date", Field.Text (Date.shortView (Date.fromTime income.time) translations))
+  [ ("id", Field.string (toString incomeId))
+  , ("amount", Field.string (toString income.amount))
+  , ("date", Field.string (Date.shortView (Date.fromTime income.time) translations))
   ]
 
-validate : Validation String Model
-validate =
-  Validate.form3 Model
-    (Validate.get "id" (Validate.maybe Validate.int))
-    (Validate.get "amount" (Validate.int `Validate.andThen` (Validate.minInt 1)))
-    (Validate.get "date" Validation.date)
+validation : Validation String Model
+validation =
+  Validate.map3 Model
+    (Validate.field "id" (Validate.maybe Validate.int))
+    (Validate.field "amount" (Validate.int |> Validate.andThen (Validate.minInt 1)))
+    (Validate.field "date" Validation.date)
diff --git a/src/client/elm/Dialog/AddIncome/View.elm b/src/client/elm/Dialog/AddIncome/View.elm
index c628d37..b413308 100644
--- a/src/client/elm/Dialog/AddIncome/View.elm
+++ b/src/client/elm/Dialog/AddIncome/View.elm
@@ -5,7 +5,6 @@ module Dialog.AddIncome.View exposing
 import Html exposing (..)
 import Html.Attributes exposing (..)
 import Html.Events exposing (..)
-import Html.App as Html
 import Task
 
 import Form exposing (Form)
@@ -31,8 +30,8 @@ import Model.View exposing (View(LoggedInView))
 import LoggedData exposing (LoggedData)
 import LoggedIn.Home.Model as HomeModel
 
-button : String -> LoggedData -> List (String, Field) -> String -> Html Msg -> Maybe String -> Html Msg
-button className loggedData initialForm title buttonContent tooltip =
+button : LoggedData -> List (String, Field) -> String -> Html Msg -> Maybe String -> Html Msg
+button loggedData initialForm title buttonContent tooltip =
   let dialogConfig =
         { className = "incomeDialog"
         , title = getMessage loggedData.translations title
@@ -46,9 +45,7 @@ button className loggedData initialForm title buttonContent tooltip =
                Just message -> Tooltip.show Msg.Tooltip message
                Nothing -> []
            )
-        ++ [ class className
-           , onClick (Msg.Dialog <| Dialog.OpenWithUpdate dialogConfig (DialogMsg.AddIncomeMsg <| Form.Reset initialForm))
-           ]
+        ++ [ onClick (Msg.Dialog <| Dialog.OpenWithUpdate dialogConfig (DialogMsg.Init "incomeamount" (DialogMsg.AddIncomeMsg <| Form.Reset initialForm))) ]
          )
         [ buttonContent ]
 
diff --git a/src/client/elm/Dialog/AddPayment/Model.elm b/src/client/elm/Dialog/AddPayment/Model.elm
index 19326f0..a287d37 100644
--- a/src/client/elm/Dialog/AddPayment/Model.elm
+++ b/src/client/elm/Dialog/AddPayment/Model.elm
@@ -4,6 +4,7 @@ module Dialog.AddPayment.Model exposing
   , initialAdd
   , initialClone
   , initialEdit
+  , validation
   )
 
 import Date exposing (Date)
@@ -16,46 +17,54 @@ import Validation
 
 import Model.Payment as Payment exposing (Payment, Frequency, PaymentId)
 import Model.Translations exposing (Translations)
+import Model.Category as Category exposing (Categories, CategoryId)
+
+import Utils.Maybe as Maybe
 
 type alias Model =
   { id : Maybe PaymentId
   , name : String
   , cost : Int
   , date : Date
+  , category : CategoryId
   , frequency : Frequency
   }
 
 init : Form String Model
-init = Form.initial [] validation
+init = Form.initial [] (validation Category.empty)
 
 initialAdd : Translations -> Date -> Frequency -> List (String, Field)
 initialAdd translations date frequency =
-  [ ("date", Field.Text (Date.shortView date translations))
-  , ("frequency", Field.Radio (toString frequency))
+  [ ("date", Field.string (Date.shortView date translations))
+  , ("frequency", Field.string (toString frequency))
+  , ("category", Field.string "")
   ]
 
-initialClone : Translations -> Date -> Payment -> List (String, Field)
-initialClone translations date payment =
-  [ ("name", Field.Text payment.name)
-  , ("cost", Field.Text (toString payment.cost))
-  , ("date", Field.Text (Date.shortView date translations))
-  , ("frequency", Field.Radio (toString payment.frequency))
+initialClone : Translations -> Date -> Maybe CategoryId -> Payment -> List (String, Field)
+initialClone translations date category payment =
+  [ ("name", Field.string payment.name)
+  , ("cost", Field.string (toString payment.cost))
+  , ("date", Field.string (Date.shortView date translations))
+  , ("frequency", Field.string (toString payment.frequency))
+  , ("category", Field.string (Maybe.map toString category |> Maybe.withDefault ""))
   ]
 
-initialEdit : Translations -> Payment -> List (String, Field)
-initialEdit translations payment =
-  [ ("id", Field.Text (toString payment.id))
-  , ("name", Field.Text payment.name)
-  , ("cost", Field.Text (toString payment.cost))
-  , ("date", Field.Text (Date.shortView payment.date translations))
-  , ("frequency", Field.Radio (toString payment.frequency))
+initialEdit : Translations -> Maybe CategoryId -> Payment -> List (String, Field)
+initialEdit translations category payment =
+  [ ("id", Field.string (toString payment.id))
+  , ("name", Field.string payment.name)
+  , ("cost", Field.string (toString payment.cost))
+  , ("date", Field.string (Date.shortView payment.date translations))
+  , ("frequency", Field.string (toString payment.frequency))
+  , ("category", Field.string (Maybe.map toString category |> Maybe.withDefault ""))
   ]
 
-validation : Validation String Model
-validation =
-  Validate.form5 Model
-    (Validate.get "id" (Validate.maybe Validate.int))
-    (Validate.get "name" (Validate.string `Validate.andThen` (Validate.nonEmpty)))
-    (Validate.get "cost" (Validate.int `Validate.andThen` (Validate.minInt 1)))
-    (Validate.get "date" Validation.date)
-    (Validate.get "frequency" Payment.validateFrequency)
+validation : Categories -> Validation String Model
+validation categories =
+  Validate.map6 Model
+    (Validate.field "id" (Validate.maybe Validate.int))
+    (Validate.field "name" (Validate.string |> Validate.andThen Validate.nonEmpty))
+    (Validate.field "cost" (Validate.int |> Validate.andThen (Validate.minInt 1)))
+    (Validate.field "date" Validation.date)
+    (Validate.field "category" (Validation.category categories))
+    (Validate.field "frequency" Payment.validateFrequency)
diff --git a/src/client/elm/Dialog/AddPayment/View.elm b/src/client/elm/Dialog/AddPayment/View.elm
index df1ad3b..078d5b7 100644
--- a/src/client/elm/Dialog/AddPayment/View.elm
+++ b/src/client/elm/Dialog/AddPayment/View.elm
@@ -2,10 +2,10 @@ module Dialog.AddPayment.View exposing
   ( button
   )
 
+import Dict
 import Html exposing (..)
 import Html.Attributes exposing (..)
 import Html.Events exposing (..)
-import Html.App as Html
 import Task
 
 import Form exposing (Form)
@@ -18,15 +18,17 @@ import Dialog.Msg as DialogMsg
 
 import Tooltip
 
-import View.Form as Form
 import View.Events exposing (onSubmitPrevDefault)
+import View.Form as Form
 
-import Msg exposing (Msg)
-import LoggedIn.Msg as LoggedInMsg
 import LoggedIn.Home.Msg as HomeMsg
+import LoggedIn.Msg as LoggedInMsg
+import Msg exposing (Msg)
 
-import Model.Translations exposing (getMessage)
+import Model.Category exposing (Categories)
 import Model.Payment as Payment exposing (Frequency(..))
+import Model.PaymentCategory exposing (PaymentCategories)
+import Model.Translations exposing (getMessage)
 import Model.View exposing (View(LoggedInView))
 
 import LoggedData exposing (LoggedData)
@@ -39,7 +41,7 @@ button loggedData initialForm title buttonContent tooltip =
         , title = getMessage loggedData.translations title
         , body = \model -> addPaymentForm loggedData model.addPayment
         , confirm = getMessage loggedData.translations "Confirm"
-        , confirmMsg = submitForm << .addPayment
+        , confirmMsg = submitForm loggedData.categories loggedData.paymentCategories << .addPayment
         , undo = getMessage loggedData.translations "Undo"
         }
   in  Html.button
@@ -48,14 +50,19 @@ button loggedData initialForm title buttonContent tooltip =
                Nothing -> []
            )
         ++ [ class "addPayment"
-           , onClick (Msg.Dialog <| Dialog.OpenWithUpdate dialogConfig (DialogMsg.AddPaymentMsg <| Form.Reset initialForm))
+           , onClick (Msg.Dialog <| Dialog.OpenWithUpdate dialogConfig (DialogMsg.Init "paymentname" (DialogMsg.AddPaymentMsg loggedData.categories loggedData.paymentCategories <| Form.Reset initialForm)))
            ]
          )
         [ buttonContent ]
 
 addPaymentForm : LoggedData -> Form String AddPayment.Model -> Html Msg
 addPaymentForm loggedData addPayment =
-  let htmlMap = Html.map (Msg.Dialog << Dialog.Update << DialogMsg.AddPaymentMsg)
+  let htmlMap = Html.map (Msg.Dialog << Dialog.Update << DialogMsg.AddPaymentMsg loggedData.categories loggedData.paymentCategories)
+      categoryOptions =
+        loggedData.categories
+          |> Dict.toList
+          |> List.sortBy (.name << Tuple.second)
+          |> List.map (\(id, category) -> (toString id, category.name))
   in  Html.form
         [ class "addPayment"
         , onSubmitPrevDefault Msg.NoOp
@@ -65,18 +72,24 @@ addPaymentForm loggedData addPayment =
         , if (Form.getFieldAsString "frequency" addPayment).value == Just (toString Punctual)
             then htmlMap <| Form.textInput loggedData.translations addPayment "payment" "date"
             else text ""
+        , htmlMap <| Form.selectInput loggedData.translations addPayment "payment" "category" categoryOptions
+
         , htmlMap <| Form.radioInputs loggedData.translations addPayment "payment" "frequency" [ toString Punctual, toString Monthly ]
-        , Form.hiddenSubmit (submitForm addPayment)
+        , Form.hiddenSubmit (submitForm loggedData.categories loggedData.paymentCategories addPayment)
         ]
 
-submitForm : Form String AddPayment.Model -> Msg
-submitForm addPayment =
+submitForm : Categories -> PaymentCategories -> Form String AddPayment.Model -> Msg
+submitForm categories paymentCategories addPayment =
   case Form.getOutput addPayment of
     Just data ->
       case data.id of
         Just paymentId ->
-          Msg.Dialog <| Dialog.UpdateAndClose <| Msg.EditPayment paymentId data.name data.cost data.date data.frequency
+          Msg.Dialog
+            <| Dialog.UpdateAndClose
+            <| Msg.EditPayment paymentId data.name data.cost data.date data.category data.frequency
         Nothing ->
-          Msg.Dialog <| Dialog.UpdateAndClose <| Msg.CreatePayment data.name data.cost data.date data.frequency
+          Msg.Dialog
+            <| Dialog.UpdateAndClose
+            <| Msg.CreatePayment data.name data.cost data.date data.category data.frequency
     Nothing ->
-      Msg.Dialog <| Dialog.Update <| DialogMsg.AddPaymentMsg <| Form.Submit
+      Msg.Dialog <| Dialog.Update <| DialogMsg.AddPaymentMsg categories paymentCategories <| Form.Submit
diff --git a/src/client/elm/Dialog/Model.elm b/src/client/elm/Dialog/Model.elm
index a3901f9..d4fd484 100644
--- a/src/client/elm/Dialog/Model.elm
+++ b/src/client/elm/Dialog/Model.elm
@@ -16,14 +16,17 @@ import Model.Translations exposing (Translations)
 
 import Dialog.AddPayment.Model as AddPayment
 import Dialog.AddIncome.Model as AddIncome
+import Dialog.AddCategory.Model as AddCategory
 
 type alias Model =
   { addPayment : Form String AddPayment.Model
   , addIncome : Form String AddIncome.Model
+  , addCategory : Form String AddCategory.Model
   }
 
 init : Model
 init =
   { addPayment = AddPayment.init
   , addIncome = AddIncome.init
+  , addCategory = AddCategory.init
   }
diff --git a/src/client/elm/Dialog/Msg.elm b/src/client/elm/Dialog/Msg.elm
index d504281..68ed146 100644
--- a/src/client/elm/Dialog/Msg.elm
+++ b/src/client/elm/Dialog/Msg.elm
@@ -4,7 +4,12 @@ module Dialog.Msg exposing
 
 import Form exposing (Form)
 
+import Model.Category exposing (Categories)
+import Model.PaymentCategory exposing (PaymentCategories)
+
 type Msg =
   NoOp
-  | AddPaymentMsg Form.Msg
+  | Init String Msg
+  | AddPaymentMsg Categories PaymentCategories Form.Msg
   | AddIncomeMsg Form.Msg
+  | AddCategoryMsg Form.Msg
diff --git a/src/client/elm/Dialog/Update.elm b/src/client/elm/Dialog/Update.elm
index d69082d..3915548 100644
--- a/src/client/elm/Dialog/Update.elm
+++ b/src/client/elm/Dialog/Update.elm
@@ -2,10 +2,19 @@ module Dialog.Update exposing
   ( update
   )
 
+import Dom exposing (Id)
 import Form exposing (Form)
+import Form.Field as Field
+import Task
 
-import Dialog.Msg as Dialog
+import Dialog.AddCategory.Model as AddCategory
+import Dialog.AddIncome.Model as AddIncome
+import Dialog.AddPayment.Model as AddPayment
 import Dialog.Model as Dialog
+import Dialog.Msg as Dialog
+
+import Model.Category exposing (Categories)
+import Model.PaymentCategory as PaymentCategory exposing (PaymentCategories)
 
 update : Dialog.Msg -> Dialog.Model -> (Dialog.Model, Cmd Dialog.Msg)
 update msg model =
@@ -16,16 +25,50 @@ update msg model =
       , Cmd.none
       )
 
-    Dialog.AddPaymentMsg formMsg ->
+    Dialog.Init inputId dialogMsg ->
+      update dialogMsg model
+        |> Tuple.mapSecond (\cmd -> Cmd.batch [cmd, inputFocus inputId])
+
+    Dialog.AddPaymentMsg categories paymentCategories formMsg ->
       ( { model
-        | addPayment = Form.update formMsg model.addPayment
+        | addPayment =
+            Form.update (AddPayment.validation categories) formMsg model.addPayment
+              |> updateCategory categories paymentCategories formMsg
         }
       , Cmd.none
       )
 
     Dialog.AddIncomeMsg formMsg ->
       ( { model
-        | addIncome = Form.update formMsg model.addIncome
+        | addIncome = Form.update AddIncome.validation formMsg model.addIncome
         }
       , Cmd.none
       )
+
+    Dialog.AddCategoryMsg formMsg ->
+      ( { model
+        | addCategory = Form.update AddCategory.validation formMsg model.addCategory
+        }
+      , Cmd.none
+      )
+
+inputFocus : Id -> Cmd Dialog.Msg
+inputFocus id =
+  Dom.focus id
+    |> Task.map (always Dialog.NoOp)
+    |> Task.onError (\_ -> Task.succeed Dialog.NoOp)
+    |> Task.perform (always Dialog.NoOp)
+
+updateCategory : Categories -> PaymentCategories -> Form.Msg -> (Form String AddPayment.Model -> Form String AddPayment.Model)
+updateCategory categories paymentCategories formMsg =
+  case formMsg of
+    Form.Input "name" Form.Text (Field.String paymentName) ->
+      case PaymentCategory.search paymentName paymentCategories of
+        Just category ->
+          Form.update
+            (AddPayment.validation categories)
+            (Form.Input "category" Form.Text (Field.String <| toString category))
+        Nothing ->
+          identity
+    _ ->
+      identity
diff --git a/src/client/elm/Init.elm b/src/client/elm/Init.elm
index 9c6fc3b..d87e870 100644
--- a/src/client/elm/Init.elm
+++ b/src/client/elm/Init.elm
@@ -5,7 +5,7 @@ module Init exposing
 
 import Time exposing (..)
 
-import Json.Decode as Json exposing ((:=))
+import Json.Decode as Decode exposing (Decoder)
 
 import Model.Translations exposing (..)
 import Model.Conf exposing (..)
@@ -20,11 +20,11 @@ type alias Init =
   , windowSize : Size
   }
 
-decoder : Json.Decoder Init
+decoder : Decoder Init
 decoder =
-  Json.object5 Init
-    ("time" := Json.float)
-    ("translations" := translationsDecoder)
-    ("conf" := confDecoder)
-    ("result" := initResultDecoder)
-    ("windowSize" := sizeDecoder)
+  Decode.map5 Init
+    (Decode.field "time" Decode.float)
+    (Decode.field "translations" translationsDecoder)
+    (Decode.field "conf" confDecoder)
+    (Decode.field "result" initResultDecoder)
+    (Decode.field "windowSize" sizeDecoder)
diff --git a/src/client/elm/LoggedData.elm b/src/client/elm/LoggedData.elm
index d4c31f1..9bb0a7f 100644
--- a/src/client/elm/LoggedData.elm
+++ b/src/client/elm/LoggedData.elm
@@ -13,6 +13,8 @@ import Model.Conf exposing (..)
 import Model.Payment exposing (Payments)
 import Model.User exposing (Users, UserId)
 import Model.Income exposing (Incomes)
+import Model.Category exposing (Categories)
+import Model.PaymentCategory exposing (PaymentCategories)
 
 import LoggedIn.Model as LoggedInModel
 
@@ -24,6 +26,8 @@ type alias LoggedData =
   , me : UserId
   , payments : Payments
   , incomes : Incomes
+  , categories : Categories
+  , paymentCategories : PaymentCategories
   }
 
 build : Model -> LoggedInModel.Model -> LoggedData
@@ -35,4 +39,6 @@ build model loggedIn =
   , me = loggedIn.me
   , payments = loggedIn.payments
   , incomes = loggedIn.incomes
+  , categories = loggedIn.categories
+  , paymentCategories = loggedIn.paymentCategories
   }
diff --git a/src/client/elm/LoggedIn/Category/Model.elm b/src/client/elm/LoggedIn/Category/Model.elm
new file mode 100644
index 0000000..7092fc4
--- /dev/null
+++ b/src/client/elm/LoggedIn/Category/Model.elm
@@ -0,0 +1,36 @@
+module LoggedIn.Category.Model exposing
+  ( Model
+  , AddCategory
+  , init
+  , initForm
+  , validation
+  )
+
+import Date exposing (Date)
+
+import Form exposing (Form)
+import Form.Validate as Validate exposing (Validation)
+import Validation
+
+type alias Model =
+  { addCategory : Form String AddCategory
+  }
+
+type alias AddCategory =
+  { amount : Int
+  , date : Date
+  }
+
+init : Model
+init =
+  { addCategory = initForm
+  }
+
+initForm : Form String AddCategory
+initForm = Form.initial [] validation
+
+validation : Validation String AddCategory
+validation =
+  Validate.map2 AddCategory
+    (Validate.field "amount" (Validate.int |> Validate.andThen (Validate.minInt 1)))
+    (Validate.field "date" Validation.date)
diff --git a/src/client/elm/LoggedIn/Category/Msg.elm b/src/client/elm/LoggedIn/Category/Msg.elm
new file mode 100644
index 0000000..3184297
--- /dev/null
+++ b/src/client/elm/LoggedIn/Category/Msg.elm
@@ -0,0 +1,9 @@
+module LoggedIn.Category.Msg exposing
+  ( Msg(..)
+  )
+
+import Form exposing (Form)
+
+type Msg =
+  NoOp
+  | AddCategoryMsg Form.Msg
diff --git a/src/client/elm/LoggedIn/Category/Table/View.elm b/src/client/elm/LoggedIn/Category/Table/View.elm
new file mode 100644
index 0000000..fa7a7b1
--- /dev/null
+++ b/src/client/elm/LoggedIn/Category/Table/View.elm
@@ -0,0 +1,124 @@
+module LoggedIn.Category.Table.View exposing
+  ( view
+  )
+
+import Dict exposing (..)
+import Date exposing (Date)
+import String exposing (append)
+
+import FontAwesome
+import View.Color as Color
+
+import Html exposing (..)
+import Html.Attributes exposing (..)
+import Html.Events exposing (..)
+
+import Dialog
+import Dialog.AddCategory.Model as AddCategory
+import Dialog.AddCategory.View as AddCategory
+
+import Tooltip
+
+import Msg exposing (Msg)
+
+import LoggedData exposing (LoggedData)
+
+import LoggedIn.Msg as LoggedInMsg
+
+import LoggedIn.Category.Model as Category
+import View.Date as Date
+import LoggedIn.View.Format as Format
+
+import Model.User exposing (getUserName)
+import Model.Category as Category exposing (CategoryId, Category)
+import Model.PaymentCategory as PaymentCategory
+import Model.Translations exposing (getMessage)
+
+view : LoggedData -> Category.Model -> Html Msg
+view loggedData categoryModel =
+  let categories =
+        loggedData.categories
+          |> Dict.toList
+          |> List.sortBy (.name << Tuple.second)
+  in  div
+        [ class "table" ]
+        [ div
+            [ class "lines" ]
+            ( headerLine loggedData :: List.map (paymentLine loggedData categoryModel) categories)
+        , if List.isEmpty (Dict.toList loggedData.categories)
+            then
+              div
+                [ class "emptyTableMsg" ]
+                [ text <| getMessage loggedData.translations "NoCategories" ]
+            else
+              text ""
+        ]
+
+headerLine : LoggedData -> Html Msg
+headerLine loggedData =
+  div
+    [ class "header" ]
+    [ div [ class "cell name" ] [ text <| getMessage loggedData.translations "Name" ]
+    , div [ class "cell category" ] [ text <| getMessage loggedData.translations "Color" ]
+    , div [ class "cell" ] []
+    , div [ class "cell" ] []
+    , div [ class "cell" ] []
+    ]
+
+paymentLine : LoggedData -> Category.Model -> (CategoryId, Category) -> Html Msg
+paymentLine loggedData categoryModel (categoryId, category) =
+  div
+    [ class "row" ]
+    [ div
+        [ class "cell category" ]
+        [ text category.name ]
+    , div
+        [ class "cell category" ]
+        [ span
+            [ class "tag"
+            , style [("background-color", category.color)]
+            ]
+            [ text category.color ]
+        ]
+    , div
+        [ class "cell button" ]
+        [ let currentDate = Date.fromTime loggedData.currentTime
+          in  AddCategory.button
+                loggedData
+                (AddCategory.initialClone loggedData.translations category)
+                "CloneCategory"
+                (FontAwesome.clone Color.chestnutRose 18)
+                (Just (getMessage loggedData.translations "Clone"))
+        ]
+    , div
+        [ class "cell button" ]
+        [ AddCategory.button
+            loggedData
+            (AddCategory.initialEdit loggedData.translations categoryId category)
+            "EditCategory"
+            (FontAwesome.pencil Color.chestnutRose 18)
+            (Just (getMessage loggedData.translations "Edit"))
+        ]
+    , div
+        [ class "cell button" ]
+        [ if PaymentCategory.isCategoryUnused categoryId loggedData.paymentCategories
+            then
+              let dialogConfig =
+                    { className = "deleteCategoryDialog"
+                    , title = getMessage loggedData.translations "ConfirmCategoryDelete"
+                    , body = always <| text ""
+                    , confirm = getMessage loggedData.translations "Confirm"
+                    , confirmMsg = always <| Msg.Dialog <| Dialog.UpdateAndClose <| Msg.DeleteCategory categoryId
+                    , undo = getMessage loggedData.translations "Undo"
+                    }
+              in  button
+                    (  Tooltip.show Msg.Tooltip (getMessage loggedData.translations "Delete")
+                    ++ [ onClick (Msg.Dialog <| Dialog.Open dialogConfig) ]
+                    )
+                    [ FontAwesome.trash Color.chestnutRose 18 ]
+          else
+            span
+              ( Tooltip.show Msg.Tooltip (getMessage loggedData.translations "UsedCategory") )
+              [ FontAwesome.trash Color.silver 18 ]
+        ]
+    ]
diff --git a/src/client/elm/LoggedIn/Category/Update.elm b/src/client/elm/LoggedIn/Category/Update.elm
new file mode 100644
index 0000000..1072ef0
--- /dev/null
+++ b/src/client/elm/LoggedIn/Category/Update.elm
@@ -0,0 +1,24 @@
+module LoggedIn.Category.Update exposing
+  ( update
+  )
+
+import Form exposing (Form)
+
+import LoggedData exposing (LoggedData)
+
+import LoggedIn.Category.Model as Category
+import LoggedIn.Category.Msg as Category
+
+update : LoggedData -> Category.Msg -> Category.Model -> (Category.Model, Cmd Category.Msg)
+update loggedData msg model =
+  case msg of
+
+    Category.NoOp ->
+      ( model
+      , Cmd.none
+      )
+
+    Category.AddCategoryMsg formMsg ->
+      ( { model | addCategory = Form.update Category.validation formMsg model.addCategory }
+      , Cmd.none
+      )
diff --git a/src/client/elm/LoggedIn/Category/View.elm b/src/client/elm/LoggedIn/Category/View.elm
new file mode 100644
index 0000000..4e04fa2
--- /dev/null
+++ b/src/client/elm/LoggedIn/Category/View.elm
@@ -0,0 +1,35 @@
+module LoggedIn.Category.View exposing
+  ( view
+  )
+
+import Html exposing (..)
+import Html.Attributes exposing (..)
+
+import LoggedData exposing (LoggedData)
+
+import Msg exposing (Msg)
+
+import Dialog.AddCategory.Model as AddCategory
+import Dialog.AddCategory.View as AddCategory
+
+import LoggedIn.Category.Model as Category
+import LoggedIn.Category.Table.View as Table
+
+import Model.Translations exposing (getMessage, getParamMessage)
+
+view : LoggedData -> Category.Model -> Html Msg
+view loggedData categoryModel =
+  div
+    [ class "categories" ]
+    [ div
+        [ class "titleButton withMargin" ]
+        [ h1 [] [ text <| getMessage loggedData.translations "Categories" ]
+        , AddCategory.button
+            loggedData
+            (AddCategory.initialAdd loggedData.translations)
+            "AddCategory"
+            (text (getMessage loggedData.translations "AddCategory"))
+            Nothing
+        ]
+    , Table.view loggedData categoryModel
+    ]
diff --git a/src/client/elm/LoggedIn/Home/Header/View.elm b/src/client/elm/LoggedIn/Home/Header/View.elm
index b67fb3b..3f8a320 100644
--- a/src/client/elm/LoggedIn/Home/Header/View.elm
+++ b/src/client/elm/LoggedIn/Home/Header/View.elm
@@ -5,7 +5,6 @@ module LoggedIn.Home.Header.View exposing
 import Html exposing (..)
 import Html.Attributes exposing (..)
 import Html.Events exposing (..)
-import Html.App as Html
 import String
 import Dict
 import Date
@@ -32,8 +31,6 @@ import LoggedIn.Home.View.ExceedingPayers as ExceedingPayers
 import LoggedIn.View.Format as Format
 import View.Plural exposing (plural)
 
-import Utils.Tuple as Tuple
-
 view : LoggedData -> Home.Model -> Payments -> Frequency -> Html Msg
 view loggedData { search } payments frequency =
   let currentDate = Date.fromTime loggedData.currentTime
@@ -90,9 +87,9 @@ paymentsPartition loggedData payments =
     ", "
     ( loggedData.users
         |> Dict.toList
-        |> List.map (Tuple.mapFst (\userId -> Payment.totalPayments (always True) userId payments))
+        |> List.map (Tuple.mapFirst (\userId -> Payment.totalPayments (always True) userId payments))
         |> List.filter (\(sum, _) -> sum > 0)
-        |> List.sortBy fst
+        |> List.sortBy Tuple.first
         |> List.reverse
         |> List.map (\(sum, user) ->
              getParamMessage [ user.name, Format.price loggedData.conf sum ] loggedData.translations "By"
diff --git a/src/client/elm/LoggedIn/Home/Model.elm b/src/client/elm/LoggedIn/Home/Model.elm
index caedc29..ace1593 100644
--- a/src/client/elm/LoggedIn/Home/Model.elm
+++ b/src/client/elm/LoggedIn/Home/Model.elm
@@ -3,6 +3,7 @@ module LoggedIn.Home.Model exposing
   , Search
   , init
   , searchInitial
+  , validation
   )
 
 import Form exposing (Form)
@@ -26,14 +27,14 @@ type alias Search =
 init : Model
 init =
   { currentPage = 1
-  , search = Form.initial (searchInitial Punctual) searchValidation
+  , search = Form.initial (searchInitial Punctual) validation
   }
 
 searchInitial : Frequency -> List (String, Field)
-searchInitial frequency = [ ("frequency", Field.Radio (toString frequency)) ]
+searchInitial frequency = [ ("frequency", Field.string (toString frequency)) ]
 
-searchValidation : Validation String Search
-searchValidation =
-  Validate.form2 Search
-    (Validate.get "name" (Validate.maybe Validate.string))
-    (Validate.get "frequency" Payment.validateFrequency)
+validation : Validation String Search
+validation =
+  Validate.map2 Search
+    (Validate.field "name" (Validate.maybe Validate.string))
+    (Validate.field "frequency" Payment.validateFrequency)
diff --git a/src/client/elm/LoggedIn/Home/Update.elm b/src/client/elm/LoggedIn/Home/Update.elm
index d1a3239..b0ce256 100644
--- a/src/client/elm/LoggedIn/Home/Update.elm
+++ b/src/client/elm/LoggedIn/Home/Update.elm
@@ -25,10 +25,10 @@ update loggedData msg model =
 
     Home.SearchMsg formMsg ->
       ( { model
-        | search = Form.update formMsg model.search
+        | search = Form.update Home.validation formMsg model.search
         , currentPage =
             case formMsg of
-              Form.Input "name" _ -> 1
+              Form.Input "name" _ _ -> 1
               _ -> model.currentPage
         }
       , Cmd.none
diff --git a/src/client/elm/LoggedIn/Home/View.elm b/src/client/elm/LoggedIn/Home/View.elm
index 0def64e..0b90e67 100644
--- a/src/client/elm/LoggedIn/Home/View.elm
+++ b/src/client/elm/LoggedIn/Home/View.elm
@@ -2,23 +2,22 @@ module LoggedIn.Home.View exposing
   ( view
   )
 
+import Date
 import Html exposing (..)
 import Html.Attributes exposing (..)
-import Date
 
 import Form
 import Utils.Form as Form
 
-import Msg exposing (Msg)
-
 import LoggedData exposing (LoggedData)
-import Model.Payment as Payment exposing (Frequency(..))
-
-import LoggedIn.Home.Model as Home
 import LoggedIn.Home.Header.View as Header
-
-import LoggedIn.Home.View.Table as Table
+import LoggedIn.Home.Model as Home
+import LoggedIn.Home.Msg as HomeMsg
 import LoggedIn.Home.View.Paging as Paging
+import LoggedIn.Home.View.Table as Table
+import LoggedIn.Msg as LoggedInMsg
+import Model.Payment as Payment exposing (Frequency(..))
+import Msg exposing (Msg)
 
 view : LoggedData -> Home.Model -> Html Msg
 view loggedData home =
@@ -31,5 +30,9 @@ view loggedData home =
         [ class "home" ]
         [ Header.view loggedData home payments frequency
         , Table.view loggedData home payments frequency
-        , Paging.view home payments
+        , Paging.view
+            home.currentPage
+            (List.length payments)
+            Msg.NoOp
+            (Msg.UpdateLoggedIn << LoggedInMsg.HomeMsg << HomeMsg.UpdatePage)
         ]
diff --git a/src/client/elm/LoggedIn/Home/View/Paging.elm b/src/client/elm/LoggedIn/Home/View/Paging.elm
index 5bcb827..dffe061 100644
--- a/src/client/elm/LoggedIn/Home/View/Paging.elm
+++ b/src/client/elm/LoggedIn/Home/View/Paging.elm
@@ -10,31 +10,29 @@ import Html exposing (..)
 import Html.Attributes exposing (..)
 import Html.Events exposing (..)
 
-import LoggedIn.Msg as LoggedInMsg
-
-import LoggedIn.Home.Msg as HomeMsg
-import LoggedIn.Home.Model as HomeModel
-
-import Msg exposing (Msg)
 import LoggedData exposing (LoggedData)
 import Model.Payment as Payment exposing (Payments, perPage)
 
 showedPages : Int
 showedPages = 5
 
-view : HomeModel.Model -> Payments -> Html Msg
-view homeModel payments =
-  let maxPage = ceiling (toFloat (List.length payments) / toFloat perPage)
-      pages = truncatePages homeModel.currentPage [1..maxPage]
+view : Int -> Int -> msg -> (Int -> msg) -> Html msg
+view currentPage payments noOp pageMsg =
+  let maxPage = ceiling (toFloat payments / toFloat perPage)
+      pages = truncatePages currentPage (List.range 1 maxPage)
   in  if maxPage <= 1
         then
           text ""
         else
           div
             [ class "pages" ]
-            (  [ firstPage homeModel, previousPage homeModel ]
-            ++ ( List.map (paymentsPage homeModel) pages)
-            ++ [ nextPage homeModel maxPage, lastPage homeModel maxPage ]
+            (  [ firstPage currentPage pageMsg
+               , previousPage currentPage noOp pageMsg
+               ]
+            ++ ( List.map (paymentsPage currentPage noOp pageMsg) pages)
+            ++ [ nextPage currentPage maxPage noOp pageMsg
+               , lastPage currentPage maxPage pageMsg
+               ]
             )
 
 truncatePages : Int -> List Int -> List Int
@@ -44,57 +42,57 @@ truncatePages currentPage pages =
       showedRightPages = floor ((toFloat showedPages - 1) / 2)
       truncatedPages =
         if currentPage <= showedLeftPages then
-          [1..showedPages]
+          (List.range 1 showedPages)
         else if currentPage > totalPages - showedRightPages then
-          [(totalPages - showedPages + 1)..totalPages]
+          (List.range (totalPages - showedPages + 1) totalPages)
         else
-          [(currentPage - showedLeftPages)..(currentPage + showedRightPages)]
+          (List.range (currentPage - showedLeftPages) (currentPage + showedRightPages))
   in  List.filter (flip List.member pages) truncatedPages
 
-firstPage : HomeModel.Model -> Html Msg
-firstPage homeModel =
+firstPage : Int -> (Int -> msg) -> Html msg
+firstPage currentPage pageMsg =
   button
     [ classList
         [ ("page", True)
-        , ("disable", homeModel.currentPage <= 1)
+        , ("disable", currentPage <= 1)
         ]
-    , onClick (Msg.UpdateLoggedIn << LoggedInMsg.HomeMsg << HomeMsg.UpdatePage <| 1)
+    , onClick (pageMsg 1)
     ]
     [ FontAwesome.fast_backward grey 13 ]
 
-previousPage : HomeModel.Model -> Html Msg
-previousPage homeModel =
+previousPage : Int -> msg -> (Int -> msg) -> Html msg
+previousPage currentPage noOp pageMsg =
   button
     [ class "page"
     , onClick <|
-        if homeModel.currentPage > 1
-          then (Msg.UpdateLoggedIn << LoggedInMsg.HomeMsg << HomeMsg.UpdatePage <| homeModel.currentPage - 1)
-          else Msg.NoOp
+        if currentPage > 1
+          then (pageMsg <| currentPage - 1)
+          else noOp
     ]
     [ FontAwesome.backward grey 13 ]
 
-nextPage : HomeModel.Model -> Int -> Html Msg
-nextPage homeModel maxPage =
+nextPage : Int -> Int -> msg -> (Int -> msg) -> Html msg
+nextPage currentPage maxPage noOp pageMsg =
   button
     [ class "page"
     , onClick <|
-        if homeModel.currentPage < maxPage
-          then (Msg.UpdateLoggedIn << LoggedInMsg.HomeMsg << HomeMsg.UpdatePage <| homeModel.currentPage + 1)
-          else Msg.NoOp
+        if currentPage < maxPage
+          then (pageMsg <| currentPage + 1)
+          else noOp
     ]
     [ FontAwesome.forward grey 13 ]
 
-lastPage : HomeModel.Model -> Int -> Html Msg
-lastPage homeModel maxPage =
+lastPage : Int -> Int -> (Int -> msg) -> Html msg
+lastPage currentPage maxPage pageMsg =
   button
     [ class "page"
-    , onClick (Msg.UpdateLoggedIn << LoggedInMsg.HomeMsg << HomeMsg.UpdatePage <| maxPage)
+    , onClick (pageMsg maxPage)
     ]
     [ FontAwesome.fast_forward grey 13 ]
 
-paymentsPage : HomeModel.Model -> Int -> Html Msg
-paymentsPage homeModel page =
-  let onCurrentPage = page == homeModel.currentPage
+paymentsPage : Int -> msg -> (Int -> msg) -> Int -> Html msg
+paymentsPage currentPage noOp pageMsg page =
+  let onCurrentPage = page == currentPage
   in  button
         [ classList
             [ ("page", True)
@@ -102,8 +100,8 @@ paymentsPage homeModel page =
             ]
         , onClick <|
             if onCurrentPage
-              then Msg.NoOp
-              else Msg.UpdateLoggedIn << LoggedInMsg.HomeMsg << HomeMsg.UpdatePage <| page
+              then noOp
+              else pageMsg page
         ]
         [ text (toString page) ]
 
diff --git a/src/client/elm/LoggedIn/Home/View/Table.elm b/src/client/elm/LoggedIn/Home/View/Table.elm
index 6423bf9..8828488 100644
--- a/src/client/elm/LoggedIn/Home/View/Table.elm
+++ b/src/client/elm/LoggedIn/Home/View/Table.elm
@@ -2,8 +2,8 @@ module LoggedIn.Home.View.Table exposing
   ( view
   )
 
-import Dict exposing (..)
 import Date exposing (Date)
+import Dict exposing (..)
 import String exposing (append)
 
 import FontAwesome
@@ -26,12 +26,13 @@ import LoggedData exposing (LoggedData)
 import LoggedIn.Msg as LoggedInMsg
 
 import LoggedIn.Home.Model as Home
-import View.Date as Date
 import LoggedIn.View.Format as Format
+import View.Date as Date
 
-import Model.User exposing (getUserName)
 import Model.Payment as Payment exposing (..)
+import Model.PaymentCategory as PaymentCategory
 import Model.Translations exposing (getMessage)
+import Model.User exposing (getUserName)
 
 view : LoggedData -> Home.Model -> Payments -> Frequency -> Html Msg
 view loggedData homeModel payments frequency =
@@ -60,6 +61,7 @@ headerLine loggedData frequency =
     [ div [ class "cell category" ] [ text <| getMessage loggedData.translations "Name" ]
     , div [ class "cell cost" ] [ text <| getMessage loggedData.translations "Cost" ]
     , div [ class "cell user" ] [ text <| getMessage loggedData.translations "Payer" ]
+    , div [ class "cell user" ] [ text <| getMessage loggedData.translations "PaymentCategory" ]
     , case frequency of
         Punctual -> div [ class "cell date" ] [ text <| getMessage loggedData.translations "Date" ]
         Monthly -> text ""
@@ -72,7 +74,7 @@ paymentLine : LoggedData -> Home.Model -> Frequency -> Payment -> Html Msg
 paymentLine loggedData homeModel frequency payment =
   div
     [ class "row" ]
-    [ div [ class "cell category" ] [ text payment.name ]
+    [ div [ class "cell name" ] [ text payment.name ]
     , div
         [ classList
             [ ("cell cost", True)
@@ -87,6 +89,22 @@ paymentLine loggedData homeModel frequency payment =
             |> Maybe.withDefault "−"
             |> text
         ]
+    , div
+        [ class "cell category" ]
+        ( let mbCategory =
+                PaymentCategory.search payment.name loggedData.paymentCategories
+                  |> Maybe.andThen (\category -> Dict.get category loggedData.categories)
+          in  case mbCategory of
+                Just category ->
+                  [ span
+                      [ class "tag"
+                      , style [("background-color", category.color)]
+                      ]
+                      [ text category.name ]
+                  ]
+                Nothing ->
+                  []
+        )
     , case frequency of
         Punctual ->
           div
@@ -103,9 +121,10 @@ paymentLine loggedData homeModel frequency payment =
     , div
         [ class "cell button" ]
         [ let currentDate = Date.fromTime loggedData.currentTime
+              category = PaymentCategory.search payment.name loggedData.paymentCategories
           in  AddPayment.button
                 loggedData
-                (AddPayment.initialClone loggedData.translations currentDate payment)
+                (AddPayment.initialClone loggedData.translations currentDate category payment)
                 "ClonePayment"
                 (FontAwesome.clone Color.chestnutRose 18)
                 (Just (getMessage loggedData.translations "Clone"))
@@ -116,12 +135,13 @@ paymentLine loggedData homeModel frequency payment =
             then
               text ""
             else
-              AddPayment.button
-                loggedData
-                (AddPayment.initialEdit loggedData.translations payment)
-                "EditPayment"
-                (FontAwesome.pencil Color.chestnutRose 18)
-                (Just (getMessage loggedData.translations "Edit"))
+              let category = PaymentCategory.search payment.name loggedData.paymentCategories
+              in  AddPayment.button
+                    loggedData
+                    (AddPayment.initialEdit loggedData.translations category payment)
+                    "EditPayment"
+                    (FontAwesome.pencil Color.chestnutRose 18)
+                    (Just (getMessage loggedData.translations "Edit"))
         ]
     , div
         [ class "cell button" ]
diff --git a/src/client/elm/LoggedIn/Income/Model.elm b/src/client/elm/LoggedIn/Income/Model.elm
index cf1bf57..7d852b9 100644
--- a/src/client/elm/LoggedIn/Income/Model.elm
+++ b/src/client/elm/LoggedIn/Income/Model.elm
@@ -3,12 +3,13 @@ module LoggedIn.Income.Model exposing
   , AddIncome
   , init
   , initForm
+  , validation
   )
 
 import Date exposing (Date)
 
 import Form exposing (Form)
-import Form.Validate as Validate exposing (..)
+import Form.Validate as Validate exposing (Validation)
 import Validation
 
 type alias Model =
@@ -26,10 +27,10 @@ init =
   }
 
 initForm : Form String AddIncome
-initForm = Form.initial [] validate
+initForm = Form.initial [] validation
 
-validate : Validation String AddIncome
-validate =
-  form2 AddIncome
-    (get "amount" (int `andThen` (minInt 1)))
-    (get "date" Validation.date)
+validation : Validation String AddIncome
+validation =
+  Validate.map2 AddIncome
+    (Validate.field "amount" (Validate.int |> Validate.andThen (Validate.minInt 1)))
+    (Validate.field "date" Validation.date)
diff --git a/src/client/elm/LoggedIn/Income/Update.elm b/src/client/elm/LoggedIn/Income/Update.elm
index ec6a0c1..0023c76 100644
--- a/src/client/elm/LoggedIn/Income/Update.elm
+++ b/src/client/elm/LoggedIn/Income/Update.elm
@@ -6,19 +6,19 @@ import Form exposing (Form)
 
 import LoggedData exposing (LoggedData)
 
-import LoggedIn.Income.Model as IncomeModel
-import LoggedIn.Income.Msg as IncomeMsg
+import LoggedIn.Income.Model as Income
+import LoggedIn.Income.Msg as Income
 
-update : LoggedData -> IncomeMsg.Msg -> IncomeModel.Model -> (IncomeModel.Model, Cmd IncomeMsg.Msg)
+update : LoggedData -> Income.Msg -> Income.Model -> (Income.Model, Cmd Income.Msg)
 update loggedData msg model =
   case msg of
 
-    IncomeMsg.NoOp ->
+    Income.NoOp ->
       ( model
       , Cmd.none
       )
 
-    IncomeMsg.AddIncomeMsg formMsg ->
-      ( { model | addIncome = Form.update formMsg model.addIncome }
+    Income.AddIncomeMsg formMsg ->
+      ( { model | addIncome = Form.update Income.validation formMsg model.addIncome }
       , Cmd.none
       )
diff --git a/src/client/elm/LoggedIn/Income/View.elm b/src/client/elm/LoggedIn/Income/View.elm
index 2c5bcaf..00a1646 100644
--- a/src/client/elm/LoggedIn/Income/View.elm
+++ b/src/client/elm/LoggedIn/Income/View.elm
@@ -12,7 +12,6 @@ import FontAwesome
 import Html exposing (..)
 import Html.Events exposing (..)
 import Html.Attributes exposing (..)
-import Html.App as Html
 
 import Form exposing (Form)
 import View.Form as Form
@@ -45,19 +44,21 @@ view : LoggedData -> Income.Model -> Html Msg
 view loggedData incomeModel =
   div
     [ class "income" ]
-    [ case useIncomesFrom loggedData.users loggedData.incomes loggedData.payments of
-        Just since -> cumulativeIncomesView loggedData since
-        Nothing -> text ""
-    , div
-        [ class "textual monthlyNetIncomes" ]
-        [ h1 [] [ text <| getMessage loggedData.translations "MonthlyNetIncomes" ]
-        , AddIncome.button
-            "addIncome"
-            loggedData
-            (AddIncome.initialAdd loggedData.translations (Date.fromTime loggedData.currentTime))
-            "AddIncome"
-            (text (getMessage loggedData.translations "AddIncome"))
-            Nothing
+    [ div
+        [ class "withMargin" ]
+        [ case useIncomesFrom loggedData.users loggedData.incomes loggedData.payments of
+            Just since -> cumulativeIncomesView loggedData since
+            Nothing -> text ""
+        , div
+            [ class "titleButton" ]
+            [ h1 [] [ text <| getMessage loggedData.translations "MonthlyNetIncomes" ]
+            , AddIncome.button
+                loggedData
+                (AddIncome.initialAdd loggedData.translations (Date.fromTime loggedData.currentTime))
+                "AddIncome"
+                (text (getMessage loggedData.translations "AddIncome"))
+                Nothing
+            ]
         ]
     , Table.view loggedData incomeModel
     ]
@@ -66,7 +67,7 @@ cumulativeIncomesView : LoggedData -> Time -> Html Msg
 cumulativeIncomesView loggedData since =
   let longDate = Date.longView (Date.fromTime since) loggedData.translations
   in  div
-        [ class "textual" ]
+        []
         [ h1 [] [ text <| getParamMessage [longDate] loggedData.translations "CumulativeIncomesSince" ]
         , ul
             []
@@ -74,7 +75,7 @@ cumulativeIncomesView loggedData since =
                 |> List.map (\(userId, user) ->
                      (user.name, userCumulativeIncomeSince loggedData.currentTime since loggedData.incomes userId)
                    )
-                |> List.sortBy snd
+                |> List.sortBy Tuple.second
                 |> List.map (\(userName, cumulativeIncome) ->
                      li
                        []
diff --git a/src/client/elm/LoggedIn/Income/View/Table.elm b/src/client/elm/LoggedIn/Income/View/Table.elm
index dcf6d78..aa5e392 100644
--- a/src/client/elm/LoggedIn/Income/View/Table.elm
+++ b/src/client/elm/LoggedIn/Income/View/Table.elm
@@ -38,7 +38,7 @@ view loggedData incomeModel =
   let incomes =
         loggedData.incomes
           |> Dict.toList
-          |> List.sortBy (.time << snd)
+          |> List.sortBy (.time << Tuple.second)
           |> List.reverse
   in  div
         [ class "table" ]
@@ -49,7 +49,7 @@ view loggedData incomeModel =
             then
               div
                 [ class "emptyTableMsg" ]
-                [ text <| getMessage loggedData.translations "NoPayment" ]
+                [ text <| getMessage loggedData.translations "NoIncome" ]
             else
               text ""
         ]
@@ -87,7 +87,6 @@ paymentLine loggedData incomeModel (incomeId, income) =
         [ class "cell button" ]
         [ let currentDate = Date.fromTime loggedData.currentTime
           in  AddIncome.button
-                ""
                 loggedData
                 (AddIncome.initialClone loggedData.translations currentDate income)
                 "CloneIncome"
@@ -101,7 +100,6 @@ paymentLine loggedData incomeModel (incomeId, income) =
               text ""
             else
               AddIncome.button
-                ""
                 loggedData
                 (AddIncome.initialEdit loggedData.translations incomeId income)
                 "EditIncome"
diff --git a/src/client/elm/LoggedIn/Model.elm b/src/client/elm/LoggedIn/Model.elm
index 11386d5..6bcb0b2 100644
--- a/src/client/elm/LoggedIn/Model.elm
+++ b/src/client/elm/LoggedIn/Model.elm
@@ -9,25 +9,34 @@ import Model.Init exposing (..)
 import Model.Payment exposing (Payments)
 import Model.User exposing (Users, UserId)
 import Model.Income exposing (Incomes)
+import Model.Category exposing (Categories)
+import Model.PaymentCategory exposing (PaymentCategories)
 
-import LoggedIn.Home.Model as HomeModel
-import LoggedIn.Income.Model as IncomeModel
+import LoggedIn.Home.Model as Home
+import LoggedIn.Income.Model as Income
+import LoggedIn.Category.Model as Categories
 
 type alias Model =
-  { home : HomeModel.Model
-  , income : IncomeModel.Model
+  { home : Home.Model
+  , income : Income.Model
+  , category : Categories.Model
   , users : Users
   , me : UserId
   , payments : Payments
   , incomes : Incomes
+  , categories : Categories
+  , paymentCategories : PaymentCategories
   }
 
 init : Init -> Model
 init initData =
-  { home = HomeModel.init
-  , income = IncomeModel.init
+  { home = Home.init
+  , income = Income.init
+  , category = Categories.init
   , users = initData.users
   , me = initData.me
   , payments = initData.payments
   , incomes = initData.incomes
+  , categories = initData.categories
+  , paymentCategories = initData.paymentCategories
   }
diff --git a/src/client/elm/LoggedIn/Msg.elm b/src/client/elm/LoggedIn/Msg.elm
index ff275e2..a1379a6 100644
--- a/src/client/elm/LoggedIn/Msg.elm
+++ b/src/client/elm/LoggedIn/Msg.elm
@@ -6,17 +6,23 @@ import Date exposing (Date)
 
 import Model.Payment exposing (PaymentId, Frequency)
 import Model.Income exposing (IncomeId)
+import Model.Category exposing (CategoryId)
 
-import LoggedIn.Home.Msg as HomeMsg
-import LoggedIn.Income.Msg as IncomeMsg
+import LoggedIn.Home.Msg as Home
+import LoggedIn.Income.Msg as Income
+import LoggedIn.Category.Msg as Categories
 
 type Msg =
   NoOp
-  | HomeMsg HomeMsg.Msg
-  | IncomeMsg IncomeMsg.Msg
-  | ValidateCreatePayment PaymentId String Int Date Frequency
-  | ValidateEditPayment PaymentId String Int Date Frequency
+  | HomeMsg Home.Msg
+  | IncomeMsg Income.Msg
+  | CategoriesMsg Categories.Msg
+  | ValidateCreatePayment PaymentId String Int Date CategoryId Frequency
+  | ValidateEditPayment PaymentId String Int Date CategoryId Frequency
   | ValidateDeletePayment PaymentId
   | ValidateCreateIncome IncomeId Int Date
   | ValidateEditIncome IncomeId Int Date
   | ValidateDeleteIncome IncomeId
+  | ValidateCreateCategory CategoryId String String
+  | ValidateEditCategory CategoryId String String
+  | ValidateDeleteCategory CategoryId
diff --git a/src/client/elm/LoggedIn/Stat/View.elm b/src/client/elm/LoggedIn/Stat/View.elm
index 946005a..f57316a 100644
--- a/src/client/elm/LoggedIn/Stat/View.elm
+++ b/src/client/elm/LoggedIn/Stat/View.elm
@@ -26,7 +26,7 @@ view loggedData =
   let paymentsByMonth = Payment.groupAndSortByMonth (Payment.punctual loggedData.payments)
       monthPaymentMean = getMonthPaymentMean loggedData paymentsByMonth
   in  div
-        [ class "stat textual" ]
+        [ class "stat withMargin" ]
         [ h1 [] [ text (getParamMessage [ Format.price loggedData.conf monthPaymentMean ] loggedData.translations "ByMonthsAndMean") ]
         , ul
             []
@@ -40,7 +40,7 @@ getMonthPaymentMean loggedData paymentsByMonth =
          let currentDate = Date.fromTime loggedData.currentTime
          in  not (Date.month currentDate == month && Date.year currentDate == year)
        )
-    |> List.map (List.sum << List.map .cost << snd)
+    |> List.map (List.sum << List.map .cost << Tuple.second)
     |> List.mean
 
 monthDetail : LoggedData -> ((Month, Int), Payments) -> Html Msg
diff --git a/src/client/elm/LoggedIn/Update.elm b/src/client/elm/LoggedIn/Update.elm
index 06cd623..9e6d6ee 100644
--- a/src/client/elm/LoggedIn/Update.elm
+++ b/src/client/elm/LoggedIn/Update.elm
@@ -15,6 +15,8 @@ import Form
 import Model exposing (Model)
 import Model.Payment as Payment exposing (Payment, Frequency(..))
 import Model.Income as Income exposing (Income)
+import Model.Category exposing (Category)
+import Model.PaymentCategory as PaymentCategory
 
 import Server
 import LoggedData
@@ -22,16 +24,16 @@ import LoggedData
 import LoggedIn.Msg as LoggedInMsg
 import LoggedIn.Model as LoggedInModel
 
-import LoggedIn.Home.Msg as HomeMsg
-import LoggedIn.Home.Update as HomeUpdate
-import LoggedIn.Home.Model as HomeModel
+import LoggedIn.Home.Msg as Home
+import LoggedIn.Home.Update as Home
+import LoggedIn.Home.Model as Home
 
-import LoggedIn.Income.Msg as IncomeMsg
-import LoggedIn.Income.Update as IncomeUpdate
+import LoggedIn.Income.Update as Income
+import LoggedIn.Income.Model as Income
 
-import LoggedIn.Income.Model as IncomeModel
+import LoggedIn.Category.Update as Categories
+import LoggedIn.Category.Model as Categories
 
-import Utils.Tuple as Tuple
 import Utils.Cmd exposing ((:>))
 
 update : Model -> LoggedInMsg.Msg -> LoggedInModel.Model -> (LoggedInModel.Model, Cmd LoggedInMsg.Msg)
@@ -45,32 +47,51 @@ update model msg loggedIn =
           )
 
         LoggedInMsg.HomeMsg homeMsg ->
-          case HomeUpdate.update loggedData homeMsg loggedIn.home of
+          case Home.update loggedData homeMsg loggedIn.home of
             (home, effects) ->
               ( { loggedIn | home = home }
               , Cmd.map LoggedInMsg.HomeMsg effects
               )
 
         LoggedInMsg.IncomeMsg incomeMsg ->
-          case IncomeUpdate.update loggedData incomeMsg loggedIn.income of
+          case Income.update loggedData incomeMsg loggedIn.income of
             (income, cmd) ->
               ( { loggedIn | income = income }
               , Cmd.map LoggedInMsg.IncomeMsg cmd
               )
 
-        LoggedInMsg.ValidateCreatePayment paymentId name cost date frequency ->
-          update model (LoggedInMsg.HomeMsg <| HomeMsg.SearchMsg (Form.Reset (HomeModel.searchInitial frequency))) loggedIn
-            :> update model (LoggedInMsg.HomeMsg <| HomeMsg.UpdatePage 1)
+        LoggedInMsg.CategoriesMsg categoriesMsg ->
+          case Categories.update loggedData categoriesMsg loggedIn.category of
+            (category, cmd) ->
+              ( { loggedIn | category = category }
+              , Cmd.map LoggedInMsg.CategoriesMsg cmd
+              )
+
+        LoggedInMsg.ValidateCreatePayment paymentId name cost date category frequency ->
+          update model (LoggedInMsg.HomeMsg <| Home.SearchMsg (Form.Reset (Home.searchInitial frequency))) loggedIn
+            :> update model (LoggedInMsg.HomeMsg <| Home.UpdatePage 1)
             :> (\loggedIn ->
                  let newPayment = Payment paymentId name cost date loggedIn.me frequency
-                 in  ( { loggedIn | payments = newPayment :: loggedIn.payments }
+                 in  ( { loggedIn
+                       | payments = newPayment :: loggedIn.payments
+                       , paymentCategories = PaymentCategory.set name category loggedIn.paymentCategories
+                       }
                      , Cmd.none
                      )
                )
 
-        LoggedInMsg.ValidateEditPayment paymentId name cost date frequency ->
+        LoggedInMsg.ValidateEditPayment paymentId name cost date category frequency ->
           let updatedPayment = Payment paymentId name cost date loggedIn.me frequency
-          in  ( { loggedIn | payments = Payment.edit updatedPayment loggedIn.payments }
+              mbOldPayment = Payment.find paymentId loggedIn.payments
+          in  ( { loggedIn
+                | payments = Payment.edit updatedPayment loggedIn.payments
+                , paymentCategories =
+                    case mbOldPayment of
+                      Just oldPayment ->
+                        PaymentCategory.update oldPayment.name name category loggedIn.paymentCategories
+                      Nothing ->
+                        loggedData.paymentCategories
+                }
               , Cmd.none
               )
 
@@ -86,7 +107,7 @@ update model msg loggedIn =
                 )
           in  if switchToPunctual
                 then
-                  update model (LoggedInMsg.HomeMsg <| HomeMsg.SearchMsg (Form.Reset (HomeModel.searchInitial Punctual))) loggedIn
+                  update model (LoggedInMsg.HomeMsg <| Home.SearchMsg (Form.Reset (Home.searchInitial Punctual))) loggedIn
                     :> (\loggedIn ->
                          ( { loggedIn | payments = payments }
                          , Cmd.none
@@ -99,20 +120,12 @@ update model msg loggedIn =
 
         LoggedInMsg.ValidateCreateIncome incomeId amount date ->
           let newIncome = { userId = loggedIn.me, amount = amount, time = Date.toTime date }
-              loggedInIncome = loggedIn.income
-          in  ( { loggedIn
-                | incomes = Dict.insert incomeId newIncome loggedIn.incomes
-                , income = { loggedInIncome | addIncome = IncomeModel.initForm }
-                }
+          in  ( { loggedIn | incomes = Dict.insert incomeId newIncome loggedIn.incomes }
               , Cmd.none
               )
 
         LoggedInMsg.ValidateEditIncome incomeId amount date ->
-          let updatedIncome = Income loggedIn.me (Date.toTime date) amount
-              updateIncome mbIncome =
-                case mbIncome of
-                  Just _ -> Just updatedIncome
-                  Nothing -> Just updatedIncome
+          let updateIncome _ = Just <| Income loggedIn.me (Date.toTime date) amount
           in  ( { loggedIn | incomes = Dict.update incomeId updateIncome loggedIn.incomes }
               , Cmd.none
               )
@@ -121,3 +134,18 @@ update model msg loggedIn =
           ( { loggedIn | incomes = Dict.remove incomeId loggedIn.incomes }
           , Cmd.none
           )
+
+        LoggedInMsg.ValidateCreateCategory categoryId name color ->
+          let newCategory = { name = name, color = color }
+          in  ( { loggedIn | categories = Dict.insert categoryId newCategory loggedIn.categories }
+              , Cmd.none
+              )
+
+        LoggedInMsg.ValidateEditCategory categoryId name color ->
+          let updateCategory _ = Just <| Category name color
+          in  ( { loggedIn | categories = Dict.update categoryId updateCategory loggedIn.categories } , Cmd.none)
+
+        LoggedInMsg.ValidateDeleteCategory categoryId ->
+          ( { loggedIn | categories = Dict.remove categoryId loggedIn.categories }
+          , Cmd.none
+          )
diff --git a/src/client/elm/LoggedIn/View.elm b/src/client/elm/LoggedIn/View.elm
index a1fa3f0..2e42a73 100644
--- a/src/client/elm/LoggedIn/View.elm
+++ b/src/client/elm/LoggedIn/View.elm
@@ -9,13 +9,15 @@ import Page
 
 import Msg exposing (Msg)
 import Model exposing (Model)
+import Model.Translations exposing (getMessage)
 import LoggedData
 
 import LoggedIn.Model as LoggedInModel
 
-import LoggedIn.Home.View as HomeView
-import LoggedIn.Income.View as UserView
-import LoggedIn.Stat.View as StatView
+import LoggedIn.Home.View as Home
+import LoggedIn.Income.View as Income
+import LoggedIn.Category.View as Categories
+import LoggedIn.Stat.View as Stat
 
 view : Model -> LoggedInModel.Model -> Html Msg
 view model loggedIn =
@@ -23,7 +25,9 @@ view model loggedIn =
     [ class "loggedIn" ]
     [ let loggedData = LoggedData.build model loggedIn
       in  case model.page of
-            Page.Home -> HomeView.view loggedData loggedIn.home
-            Page.Income -> UserView.view loggedData loggedIn.income
-            Page.Statistics -> StatView.view loggedData
+            Page.Home -> Home.view loggedData loggedIn.home
+            Page.Income -> Income.view loggedData loggedIn.income
+            Page.Categories -> Categories.view loggedData loggedIn.category
+            Page.Statistics -> Stat.view loggedData
+            Page.NotFound -> div [] [ text (getMessage model.translations "PageNotFound") ]
     ]
diff --git a/src/client/elm/Main.elm b/src/client/elm/Main.elm
index fa1415d..9674b66 100644
--- a/src/client/elm/Main.elm
+++ b/src/client/elm/Main.elm
@@ -4,20 +4,19 @@ module Main exposing
 
 import Navigation
 import Time
-import Msg
+import Msg exposing (Msg(UpdatePage))
 
 import Model exposing (init)
-import Update exposing (update, urlUpdate)
+import Update exposing (update)
 import View exposing (view)
 import Page
 import Tooltip
 
 main =
-  Navigation.programWithFlags (Navigation.makeParser Page.fromHash)
+  Navigation.programWithFlags (UpdatePage << Page.fromLocation)
     { init = init
     , view = view
     , update = update
-    , urlUpdate = urlUpdate
     , subscriptions = (\model ->
         Sub.batch
           [ Time.every 1000 Msg.UpdateTime
diff --git a/src/client/elm/Model.elm b/src/client/elm/Model.elm
index a1d2bff..5167e42 100644
--- a/src/client/elm/Model.elm
+++ b/src/client/elm/Model.elm
@@ -4,9 +4,11 @@ module Model exposing
   )
 
 import Time exposing (Time)
-import Json.Decode as Json
+import Json.Decode as Decode
 
-import Html.App as Html
+import Navigation exposing (Location)
+
+import Html as Html
 
 import Page exposing (Page)
 import Init as Init exposing (Init)
@@ -38,14 +40,10 @@ type alias Model =
   , tooltip : Tooltip.Model
   }
 
-init : Json.Value -> Result String Page -> (Model, Cmd Msg)
-init payload result =
-  let page =
-        case result of
-          Err _ -> Page.Home
-          Ok page -> page
-      model =
-        case Json.decodeValue Init.decoder payload of
+init : Decode.Value -> Location -> (Model, Cmd Msg)
+init payload location =
+  let model =
+        case Decode.decodeValue Init.decoder payload of
           Ok { time, translations, conf, result, windowSize } ->
             { view =
                 case result of
@@ -58,7 +56,7 @@ init payload result =
             , currentTime = time
             , translations = translations
             , conf = conf
-            , page = page
+            , page = Page.fromLocation location
             , errors = []
             , dialog = Dialog.init DialogModel.init Msg.Dialog
             , tooltip = Tooltip.init windowSize.width windowSize.height
@@ -68,7 +66,7 @@ init payload result =
             , currentTime = 0
             , translations = []
             , conf = { currency = "" }
-            , page = page
+            , page = Page.fromLocation location
             , errors = [ error ]
             , dialog = Dialog.init DialogModel.init Msg.Dialog
             , tooltip = Tooltip.init 0 0
diff --git a/src/client/elm/Model/Category.elm b/src/client/elm/Model/Category.elm
new file mode 100644
index 0000000..8b653a7
--- /dev/null
+++ b/src/client/elm/Model/Category.elm
@@ -0,0 +1,35 @@
+module Model.Category exposing
+  ( Categories
+  , Category
+  , CategoryId
+  , categoriesDecoder
+  , categoryIdDecoder
+  , empty
+  )
+
+import Json.Decode as Decode exposing (Decoder)
+import Utils.Json as Json
+import Dict exposing (Dict)
+
+type alias Categories = Dict CategoryId Category
+
+type alias CategoryId = Int
+
+type alias Category =
+  { name : String
+  , color : String
+  }
+
+categoriesDecoder : Decoder Categories
+categoriesDecoder =
+  Json.dictDecoder (Decode.field "id" categoryIdDecoder) <|
+    Decode.map2
+      Category
+        (Decode.field "name" Decode.string)
+        (Decode.field "color" Decode.string)
+
+categoryIdDecoder : Decoder CategoryId
+categoryIdDecoder = Decode.int
+
+empty : Categories
+empty = Dict.empty
diff --git a/src/client/elm/Model/Conf.elm b/src/client/elm/Model/Conf.elm
index ec04622..308fa04 100644
--- a/src/client/elm/Model/Conf.elm
+++ b/src/client/elm/Model/Conf.elm
@@ -3,11 +3,11 @@ module Model.Conf exposing
   , confDecoder
   )
 
-import Json.Decode exposing (..)
+import Json.Decode as Decode exposing (Decoder)
 
 type alias Conf =
   { currency : String
   }
 
 confDecoder : Decoder Conf
-confDecoder = object1 Conf ("currency" := string)
+confDecoder = Decode.map Conf (Decode.field "currency" Decode.string)
diff --git a/src/client/elm/Model/Date.elm b/src/client/elm/Model/Date.elm
index f3c9b91..bfba02f 100644
--- a/src/client/elm/Model/Date.elm
+++ b/src/client/elm/Model/Date.elm
@@ -4,12 +4,12 @@ module Model.Date exposing
   )
 
 import Date as Date exposing (Date)
+import Json.Decode as Decode exposing (Decoder)
+import Json.Decode.Extra as Decode
 import Time exposing (Time)
 
-import Json.Decode as Json exposing (..)
-
 timeDecoder : Decoder Time
-timeDecoder = Json.map Date.toTime dateDecoder
+timeDecoder = Decode.map Date.toTime dateDecoder
 
 dateDecoder : Decoder Date
-dateDecoder = customDecoder string Date.fromString
+dateDecoder = Decode.string |> Decode.andThen (Date.fromString >> Decode.fromResult)
diff --git a/src/client/elm/Model/Income.elm b/src/client/elm/Model/Income.elm
index a5ca34b..34578c6 100644
--- a/src/client/elm/Model/Income.elm
+++ b/src/client/elm/Model/Income.elm
@@ -9,7 +9,8 @@ module Model.Income exposing
   , cumulativeIncomesSince
   )
 
-import Json.Decode as Json exposing ((:=))
+import Json.Decode as Decode exposing (Decoder)
+import Utils.Json as Json
 import Time exposing (Time, hour)
 import List exposing (..)
 import Dict exposing (Dict)
@@ -17,7 +18,7 @@ import Dict exposing (Dict)
 import Model.Date exposing (timeDecoder)
 import Model.User exposing (UserId, userIdDecoder)
 
-import Utils.Maybe exposing (isJust, catMaybes, maybeToList)
+import Utils.Maybe as Maybe
 
 type alias Incomes = Dict IncomeId Income
 
@@ -29,31 +30,23 @@ type alias Income =
   , amount : Int
   }
 
-incomesDecoder : Json.Decoder Incomes
-incomesDecoder = Json.map Dict.fromList (Json.list incomeWithIdDecoder)
+incomesDecoder : Decoder Incomes
+incomesDecoder =
+  Json.dictDecoder (Decode.field "id" incomeIdDecoder) <|
+    Decode.map3 Income
+      (Decode.field "userId" userIdDecoder)
+      (Decode.field "date" timeDecoder)
+      (Decode.field "amount" Decode.int)
 
-incomeWithIdDecoder : Json.Decoder (IncomeId, Income)
-incomeWithIdDecoder =
-  Json.object2 (,)
-    ("id" := incomeIdDecoder)
-    incomeDecoder
-
-incomeIdDecoder : Json.Decoder IncomeId
-incomeIdDecoder = Json.int
-
-incomeDecoder : Json.Decoder Income
-incomeDecoder =
-  Json.object3 Income
-    ("userId" := userIdDecoder)
-    ("date" := timeDecoder)
-    ("amount" := Json.int)
+incomeIdDecoder : Decoder IncomeId
+incomeIdDecoder = Decode.int
 
 incomeDefinedForAll : List UserId -> Incomes -> Maybe Time
 incomeDefinedForAll userIds incomes =
   let userIncomes = List.map (\userId -> List.filter ((==) userId << .userId) << Dict.values <| incomes) userIds
       firstIncomes = map (head << sortBy .time) userIncomes
-  in  if all isJust firstIncomes
-        then head << reverse << List.sort << map .time << catMaybes <| firstIncomes
+  in  if all Maybe.isJust firstIncomes
+        then head << reverse << List.sort << map .time << Maybe.cat <| firstIncomes
         else Nothing
 
 userCumulativeIncomeSince : Time -> Time -> Incomes -> UserId -> Int
@@ -71,7 +64,7 @@ getOrderedIncomesSince : Time -> List Income -> List Income
 getOrderedIncomesSince time incomes =
   let mbStarterIncome = getIncomeAt time incomes
       orderedIncomesSince = filter (\income -> income.time >= time) incomes
-  in  (maybeToList mbStarterIncome) ++ orderedIncomesSince
+  in  (Maybe.toList mbStarterIncome) ++ orderedIncomesSince
 
 getIncomeAt : Time -> List Income -> Maybe Income
 getIncomeAt time incomes =
diff --git a/src/client/elm/Model/Init.elm b/src/client/elm/Model/Init.elm
index 3a86dba..db7069f 100644
--- a/src/client/elm/Model/Init.elm
+++ b/src/client/elm/Model/Init.elm
@@ -3,23 +3,29 @@ module Model.Init exposing
   , initDecoder
   )
 
-import Json.Decode as Json exposing ((:=))
+import Json.Decode as Decode exposing (Decoder)
 
 import Model.Payment exposing (Payments, paymentsDecoder)
-import Model.Income exposing (Incomes, incomesDecoder)
 import Model.User exposing (Users, UserId, usersDecoder, userIdDecoder)
+import Model.Income exposing (Incomes, incomesDecoder)
+import Model.Category exposing (Categories, categoriesDecoder)
+import Model.PaymentCategory exposing (PaymentCategories, paymentCategoriesDecoder)
 
 type alias Init =
   { users : Users
   , me : UserId
   , payments : Payments
   , incomes : Incomes
+  , categories : Categories
+  , paymentCategories : PaymentCategories
   }
 
-initDecoder : Json.Decoder Init
+initDecoder : Decoder Init
 initDecoder =
-  Json.object4 Init
-    ("users" := usersDecoder)
-    ("me" := userIdDecoder)
-    ("payments" := paymentsDecoder)
-    ("incomes" := incomesDecoder)
+  Decode.map6 Init
+    (Decode.field "users" usersDecoder)
+    (Decode.field "me" userIdDecoder)
+    (Decode.field "payments" paymentsDecoder)
+    (Decode.field "incomes" incomesDecoder)
+    (Decode.field "categories" categoriesDecoder)
+    (Decode.field "paymentCategories" paymentCategoriesDecoder)
diff --git a/src/client/elm/Model/InitResult.elm b/src/client/elm/Model/InitResult.elm
index c8da533..7ce0be2 100644
--- a/src/client/elm/Model/InitResult.elm
+++ b/src/client/elm/Model/InitResult.elm
@@ -3,7 +3,7 @@ module Model.InitResult exposing
   , initResultDecoder
   )
 
-import Json.Decode as Json exposing ((:=))
+import Json.Decode as Decode exposing (Decoder)
 
 import Model.Init exposing (Init, initDecoder)
 
@@ -12,17 +12,17 @@ type InitResult =
   | InitSuccess Init
   | InitError String
 
-initResultDecoder : Json.Decoder InitResult
-initResultDecoder = ("tag" := Json.string) `Json.andThen` initResultDecoderWithTag
+initResultDecoder : Decoder InitResult
+initResultDecoder = (Decode.field "tag" Decode.string) |> Decode.andThen initResultDecoderWithTag
 
-initResultDecoderWithTag : String -> Json.Decoder InitResult
+initResultDecoderWithTag : String -> Decoder InitResult
 initResultDecoderWithTag tag =
   case tag of
     "InitEmpty" ->
-      Json.succeed InitEmpty
+      Decode.succeed InitEmpty
     "InitSuccess" ->
-      Json.map InitSuccess ("contents" := initDecoder)
+      Decode.map InitSuccess (Decode.field "contents" initDecoder)
     "InitError" ->
-      Json.map InitError ("contents" := Json.string)
+      Decode.map InitError (Decode.field "contents" Decode.string)
     _ ->
-      Json.fail <| "got " ++ tag ++ " for InitResult"
+      Decode.fail <| "got " ++ tag ++ " for InitResult"
diff --git a/src/client/elm/Model/Payer.elm b/src/client/elm/Model/Payer.elm
index e5a4b65..1663273 100644
--- a/src/client/elm/Model/Payer.elm
+++ b/src/client/elm/Model/Payer.elm
@@ -6,7 +6,6 @@ module Model.Payer exposing
   , useIncomesFrom
   )
 
-import Json.Decode as Json exposing (..)
 import Dict exposing (..)
 import List
 import Maybe
@@ -54,7 +53,7 @@ getOrderedExceedingPayers currentTime users incomes payments =
               mbMaxRatio =
                 postPaymentPayers
                   |> Dict.toList
-                  |> List.map (.ratio << snd)
+                  |> List.map (.ratio << Tuple.second)
                   |> List.maximum
           in  case mbMaxRatio of
                 Just maxRatio ->
@@ -110,15 +109,15 @@ getPayers currentTime users incomes payments =
 
 exceedingPayersFromAmounts : List (UserId, Int) -> List ExceedingPayer
 exceedingPayersFromAmounts userAmounts =
-  let mbMinAmount = List.minimum << List.map snd <| userAmounts
+  let mbMinAmount = List.minimum << List.map Tuple.second <| userAmounts
   in  case mbMinAmount of
         Nothing ->
           []
         Just minAmount ->
           userAmounts
             |> List.map (\userAmount ->
-                 { userId = fst userAmount
-                 , amount = snd userAmount - minAmount
+                 { userId = Tuple.first userAmount
+                 , amount = Tuple.second userAmount - minAmount
                  }
                )
             |> List.filter (\payer -> payer.amount > 0)
diff --git a/src/client/elm/Model/Payment.elm b/src/client/elm/Model/Payment.elm
index 5109b2f..f61ded8 100644
--- a/src/client/elm/Model/Payment.elm
+++ b/src/client/elm/Model/Payment.elm
@@ -6,6 +6,7 @@ module Model.Payment exposing
   , Frequency(..)
   , paymentsDecoder
   , paymentIdDecoder
+  , find
   , edit
   , delete
   , totalPayments
@@ -18,15 +19,16 @@ module Model.Payment exposing
 
 import Date exposing (..)
 import Date.Extra.Core exposing (monthToInt, intToMonth)
-import Json.Decode as Json exposing ((:=))
-import String
+import Json.Decode as Decode exposing (Decoder)
+import Json.Decode.Extra as Decode
 import List
 
 import Form.Validate as Validate exposing (Validation)
-import Model.User exposing (UserId, userIdDecoder)
 import Model.Date exposing (dateDecoder)
+import Model.User exposing (UserId, userIdDecoder)
 
 import Utils.List as List
+import Utils.Search as Search
 
 perPage : Int
 perPage = 7
@@ -46,31 +48,36 @@ type alias PaymentId = Int
 
 type Frequency = Punctual | Monthly
 
-paymentsDecoder : Json.Decoder Payments
-paymentsDecoder = Json.list paymentDecoder
+paymentsDecoder : Decoder Payments
+paymentsDecoder = Decode.list paymentDecoder
 
-paymentDecoder : Json.Decoder Payment
+paymentDecoder : Decoder Payment
 paymentDecoder =
-  Json.object6 Payment
-    ("id" := paymentIdDecoder)
-    ("name" := Json.string)
-    ("cost" := Json.int)
-    ("date" := dateDecoder)
-    ("userId" := userIdDecoder)
-    ("frequency" := frequencyDecoder)
-
-paymentIdDecoder : Json.Decoder PaymentId
-paymentIdDecoder = Json.int
-
-frequencyDecoder : Json.Decoder Frequency
+  Decode.map6 Payment
+    (Decode.field "id" paymentIdDecoder)
+    (Decode.field "name" Decode.string)
+    (Decode.field "cost" Decode.int)
+    (Decode.field "date" dateDecoder)
+    (Decode.field "userId" userIdDecoder)
+    (Decode.field "frequency" frequencyDecoder)
+
+paymentIdDecoder : Decoder PaymentId
+paymentIdDecoder = Decode.int
+
+frequencyDecoder : Decoder Frequency
 frequencyDecoder =
-  Json.customDecoder
-    Json.string
-    (\input -> case input of
-      "Punctual" -> Ok Punctual
-      "Monthly" -> Ok Monthly
-      _ -> Err ("Could not deduce Punctual nor Monthly from " ++ input)
-    )
+  let frequencyResult input =
+        case input of
+          "Punctual" -> Ok Punctual
+          "Monthly" -> Ok Monthly
+          _ -> Err ("Could not deduce Punctual nor Monthly from " ++ input)
+  in  Decode.string |> Decode.andThen (Decode.fromResult << frequencyResult)
+
+find : PaymentId -> Payments -> Maybe Payment
+find paymentId payments =
+  payments
+    |> List.filter (\p -> p.id == paymentId)
+    |> List.head
 
 edit : Payment -> Payments -> Payments
 edit payment payments = payment :: delete payment.id payments
@@ -98,7 +105,7 @@ groupAndSortByMonth : Payments -> List ((Month, Int), Payments)
 groupAndSortByMonth payments =
   payments
     |> List.groupBy (\payment -> (Date.year payment.date, monthToInt << Date.month <| payment.date))
-    |> List.sortBy fst
+    |> List.sortBy Tuple.first
     |> List.map (\((year, month), payments) -> ((intToMonth month, year), payments))
     |> List.reverse
 
@@ -118,7 +125,7 @@ paymentSort frequency =
 searchSuccess : String -> Payment -> Bool
 searchSuccess search { name, cost } =
   let searchSuccessWord word =
-        (  String.contains (String.toLower word) (String.toLower name)
+        (  String.contains (Search.format word) (Search.format name)
         || String.contains word (toString cost)
         )
   in  List.all searchSuccessWord (String.words search)
diff --git a/src/client/elm/Model/PaymentCategory.elm b/src/client/elm/Model/PaymentCategory.elm
new file mode 100644
index 0000000..87678fe
--- /dev/null
+++ b/src/client/elm/Model/PaymentCategory.elm
@@ -0,0 +1,48 @@
+module Model.PaymentCategory exposing
+  ( PaymentCategories
+  , paymentCategoriesDecoder
+  , search
+  , isCategoryUnused
+  , set
+  , update
+  )
+
+import Dict exposing (Dict)
+import Json.Decode as Decode exposing (Decoder)
+
+import Model.Category exposing (CategoryId, categoryIdDecoder)
+import Utils.Json as Json
+import Utils.Search as Search
+
+type alias PaymentCategories = List PaymentCategory
+
+type alias PaymentCategory =
+  { name : String
+  , category : CategoryId
+  }
+
+paymentCategoriesDecoder : Decoder PaymentCategories
+paymentCategoriesDecoder =
+  Decode.list <| Decode.map2 PaymentCategory
+    (Decode.field "name" Decode.string)
+    (Decode.field "category" categoryIdDecoder)
+
+search : String -> PaymentCategories -> Maybe CategoryId
+search paymentName paymentCategories =
+  paymentCategories
+    |> List.filter (\pc -> Search.format pc.name == Search.format paymentName)
+    |> List.head
+    |> Maybe.map .category
+
+isCategoryUnused : CategoryId -> PaymentCategories -> Bool
+isCategoryUnused category paymentCategories =
+  paymentCategories
+    |> List.filter ((==) category << .category)
+    |> List.isEmpty
+
+set : String -> CategoryId -> PaymentCategories -> PaymentCategories
+set name category paymentCategories = update name name category paymentCategories
+
+update : String -> String -> CategoryId -> PaymentCategories -> PaymentCategories
+update oldName newName category paymentCategories =
+  { name = newName, category = category } :: List.filter (\pc -> not <| Search.format pc.name == Search.format oldName) paymentCategories
diff --git a/src/client/elm/Model/Size.elm b/src/client/elm/Model/Size.elm
index b29e90b..f40fb01 100644
--- a/src/client/elm/Model/Size.elm
+++ b/src/client/elm/Model/Size.elm
@@ -3,15 +3,15 @@ module Model.Size exposing
   , sizeDecoder
   )
 
-import Json.Decode as Json exposing ((:=))
+import Json.Decode as Decode exposing (Decoder)
 
 type alias Size =
   { width: Int
   , height: Int
   }
 
-sizeDecoder : Json.Decoder Size
+sizeDecoder : Decoder Size
 sizeDecoder =
-  Json.object2 Size
-    ("width" := Json.int)
-    ("height" := Json.int)
+  Decode.map2 Size
+    (Decode.field "width" Decode.int)
+    (Decode.field "height" Decode.int)
diff --git a/src/client/elm/Model/Translations.elm b/src/client/elm/Model/Translations.elm
index 57409b0..9b314e1 100644
--- a/src/client/elm/Model/Translations.elm
+++ b/src/client/elm/Model/Translations.elm
@@ -7,13 +7,13 @@ module Model.Translations exposing
   )
 
 import Maybe exposing (withDefault)
-import Json.Decode as Json exposing ((:=))
+import Json.Decode as Decode exposing (Decoder)
 import String
 
 type alias Translations = List Translation
 
-translationsDecoder : Json.Decoder Translations
-translationsDecoder = Json.list translationDecoder
+translationsDecoder : Decoder Translations
+translationsDecoder = Decode.list translationDecoder
 
 type alias Translation =
   { key : String
@@ -27,25 +27,24 @@ getTranslation key translations =
     |> List.head
     |> Maybe.map .message
 
-translationDecoder : Json.Decoder Translation
+translationDecoder : Decoder Translation
 translationDecoder =
-  Json.object2 Translation
-    ("key" := Json.string)
-    ("message" := Json.list partDecoder)
+  Decode.map2 Translation
+    (Decode.field "key" Decode.string)
+    (Decode.field "message" (Decode.list partDecoder))
 
 type MessagePart =
   Order Int
   | Str String
 
-partDecoder : Json.Decoder MessagePart
-partDecoder =
-  ("tag" := Json.string) `Json.andThen` partDecoderWithTag
+partDecoder : Decoder MessagePart
+partDecoder = (Decode.field "tag" Decode.string) |> Decode.andThen partDecoderWithTag
 
-partDecoderWithTag : String -> Json.Decoder MessagePart
+partDecoderWithTag : String -> Decoder MessagePart
 partDecoderWithTag tag =
   case tag of
-    "Order" -> Json.object1 Order ("contents" := Json.int)
-    _ -> Json.object1 Str ("contents" := Json.string)
+    "Order" -> Decode.map Order (Decode.field "contents" Decode.int)
+    _ -> Decode.map Str (Decode.field "contents" Decode.string)
 
 -----
 
diff --git a/src/client/elm/Model/User.elm b/src/client/elm/Model/User.elm
index 02f2cea..f6e8147 100644
--- a/src/client/elm/Model/User.elm
+++ b/src/client/elm/Model/User.elm
@@ -8,7 +8,7 @@ module Model.User exposing
   , getUserName
   )
 
-import Json.Decode as Json exposing ((:=))
+import Json.Decode as Decode exposing (Decoder)
 import Dict exposing (Dict)
 
 type alias Users = Dict UserId User
@@ -20,23 +20,23 @@ type alias User =
   , email : String
   }
 
-usersDecoder : Json.Decoder Users
-usersDecoder = Json.map Dict.fromList (Json.list userWithIdDecoder)
+usersDecoder : Decoder Users
+usersDecoder = Decode.map Dict.fromList (Decode.list userWithIdDecoder)
 
-userWithIdDecoder : Json.Decoder (UserId, User)
+userWithIdDecoder : Decode.Decoder (UserId, User)
 userWithIdDecoder =
-  Json.object2 (,)
-    ("id" := userIdDecoder)
+  Decode.map2 (,)
+    (Decode.field "id" userIdDecoder)
     userDecoder
 
-userIdDecoder : Json.Decoder UserId
-userIdDecoder = Json.int
+userIdDecoder : Decoder UserId
+userIdDecoder = Decode.int
 
-userDecoder : Json.Decoder User
+userDecoder : Decoder User
 userDecoder =
-  Json.object2 User
-    ("name" := Json.string)
-    ("email" := Json.string)
+  Decode.map2 User
+    (Decode.field "name" Decode.string)
+    (Decode.field "email" Decode.string)
 
 getUserName : Users -> UserId -> Maybe String
 getUserName users userId =
diff --git a/src/client/elm/Msg.elm b/src/client/elm/Msg.elm
index 49d13ca..cf592aa 100644
--- a/src/client/elm/Msg.elm
+++ b/src/client/elm/Msg.elm
@@ -10,6 +10,7 @@ import Page exposing (Page)
 import Model.Init exposing (Init)
 import Model.Payment exposing (PaymentId, Frequency)
 import Model.Income exposing (IncomeId)
+import Model.Category exposing (CategoryId)
 
 import Dialog
 import Dialog.Model as DialogModel
@@ -22,19 +23,26 @@ import LoggedIn.Msg as LoggedInMsg
 
 type Msg =
   NoOp
+  | UpdatePage Page
   | SignIn String
   | UpdateTime Time
   | GoLoggedInView Init
   | UpdateSignIn SignInMsg.Msg
   | UpdateLoggedIn LoggedInMsg.Msg
-  | CreatePayment String Int Date Frequency
-  | EditPayment PaymentId String Int Date Frequency
-  | DeletePayment PaymentId
-  | CreateIncome Int Date
-  | EditIncome IncomeId Int Date
-  | DeleteIncome IncomeId
   | GoSignInView
   | SignOut
   | Error String
   | Dialog (Dialog.Msg DialogModel.Model DialogMsg.Msg Msg)
   | Tooltip Tooltip.Msg
+
+  | CreatePayment String Int Date CategoryId Frequency
+  | EditPayment PaymentId String Int Date CategoryId Frequency
+  | DeletePayment PaymentId
+
+  | CreateIncome Int Date
+  | EditIncome IncomeId Int Date
+  | DeleteIncome IncomeId
+
+  | CreateCategory String String
+  | EditCategory CategoryId String String
+  | DeleteCategory CategoryId
diff --git a/src/client/elm/Page.elm b/src/client/elm/Page.elm
index 7cfbbc7..39232e0 100644
--- a/src/client/elm/Page.elm
+++ b/src/client/elm/Page.elm
@@ -1,32 +1,43 @@
 module Page exposing
   ( Page(..)
   , toHash
-  , fromHash
+  , fromLocation
   )
 
-import Navigation
-import UrlParser exposing (..)
+import Navigation exposing (Location)
+import UrlParser exposing (Parser, (</>), s)
 import String
 
 type Page =
   Home
   | Income
+  | Categories
   | Statistics
+  | NotFound
 
 toHash : Page -> String
 toHash page =
   case page of
     Home -> "#"
     Income -> "#income"
+    Categories -> "#categories"
     Statistics -> "#statistics"
+    NotFound -> "#notFound"
 
-fromHash : Navigation.Location -> Result String Page
-fromHash location = UrlParser.parse identity pageParser (String.dropLeft 1 location.hash)
+fromLocation : Location -> Page
+fromLocation location =
+  if location.hash == ""
+    then
+      Home
+    else
+      case UrlParser.parseHash pageParser location of
+        Just page -> page
+        Nothing -> NotFound
 
 pageParser : Parser (Page -> a) a
 pageParser =
-  oneOf
-    [ format Home (s "")
-    , format Income (s "income")
-    , format Statistics (s "statistics")
+  UrlParser.oneOf
+    [ UrlParser.map Income (s "income")
+    , UrlParser.map Categories (s "categories")
+    , UrlParser.map Statistics (s "statistics")
     ]
diff --git a/src/client/elm/Server.elm b/src/client/elm/Server.elm
index c017548..7f25876 100644
--- a/src/client/elm/Server.elm
+++ b/src/client/elm/Server.elm
@@ -6,14 +6,17 @@ module Server exposing
   , createIncome
   , editIncome
   , deleteIncome
+  , createCategory
+  , editCategory
+  , deleteCategory
   , signOut
   )
 
 import Task as Task exposing (Task)
-import Http
+import Http exposing (Error)
 import Date
-import Json.Decode exposing ((:=))
-import Json.Encode as Json
+import Json.Decode as Decode
+import Json.Encode as Encode
 import Date exposing (Date)
 
 import Date.Extra.Format as DateFormat
@@ -21,68 +24,91 @@ import Date.Extra.Format as DateFormat
 import Utils.Http as HttpUtils
 
 import Model.Payment exposing (..)
-import Model.Income exposing (incomesDecoder, incomeIdDecoder, IncomeId)
+import Model.Income exposing (incomeIdDecoder, IncomeId)
+import Model.Category exposing (categoryIdDecoder, CategoryId)
 import Model.User exposing (Users, usersDecoder, UserId, userIdDecoder)
 import Model.Init exposing (Init)
 
-signIn : String -> Task Http.Error ()
-signIn email =
-  HttpUtils.request "POST" ("/signIn?email=" ++ email)
-    |> Task.map (always ())
+signIn : String -> (Result Error String -> msg) -> Cmd msg
+signIn email = HttpUtils.request "POST" ("/signIn?email=" ++ email) Http.expectString
 
-createPayment : String -> Int -> Date -> Frequency -> Task Http.Error PaymentId
-createPayment name cost date frequency =
-  Json.object
-    [ ("name", Json.string name)
-    , ("cost", Json.int cost)
-    , ("date", Json.string (DateFormat.isoDateString date))
-    , ("frequency", Json.string (toString frequency))
-    ]
-    |> HttpUtils.jsonRequest "POST" "/payment"
-    |> flip Task.andThen (HttpUtils.decodeHttpValue <| "id" := paymentIdDecoder)
+createPayment : String -> Int -> Date -> CategoryId -> Frequency -> (Result Error PaymentId -> msg) -> Cmd msg
+createPayment name cost date categoryId frequency handleResult =
+  let json =
+        Encode.object
+          [ ("name", Encode.string name)
+          , ("cost", Encode.int cost)
+          , ("date", Encode.string (DateFormat.isoDateString date))
+          , ("category", Encode.int categoryId)
+          , ("frequency", Encode.string (toString frequency))
+          ]
+      expect = Http.expectJson (Decode.field "id" paymentIdDecoder)
+  in  HttpUtils.jsonRequest "POST" "/payment" expect handleResult json
 
-editPayment : PaymentId -> String -> Int -> Date -> Frequency -> Task Http.Error ()
-editPayment paymentId name cost date frequency =
-  Json.object
-    [ ("id", Json.int paymentId)
-    , ("name", Json.string name)
-    , ("cost", Json.int cost)
-    , ("date", Json.string (DateFormat.isoDateString date))
-    , ("frequency", Json.string (toString frequency))
-    ]
-    |> HttpUtils.jsonRequest "PUT" "/payment"
-    |> Task.map (always ())
+editPayment : PaymentId -> String -> Int -> Date -> CategoryId -> Frequency -> (Result Error String -> msg) -> Cmd msg
+editPayment paymentId name cost date categoryId frequency handleResult =
+  let json =
+        Encode.object
+          [ ("id", Encode.int paymentId)
+          , ("name", Encode.string name)
+          , ("cost", Encode.int cost)
+          , ("date", Encode.string (DateFormat.isoDateString date))
+          , ("category", Encode.int categoryId)
+          , ("frequency", Encode.string (toString frequency))
+          ]
+  in  HttpUtils.jsonRequest "PUT" "/payment" Http.expectString handleResult json
 
-deletePayment : PaymentId -> Task Http.Error ()
+deletePayment : PaymentId -> (Result Error String -> msg) -> Cmd msg
 deletePayment paymentId =
-  HttpUtils.request "DELETE" ("/payment?id=" ++ (toString paymentId))
-    |> Task.map (always ())
+  HttpUtils.request "DELETE" ("/payment?id=" ++ (toString paymentId)) Http.expectString
 
-createIncome : Int -> Date -> Task Http.Error IncomeId
-createIncome amount date =
-  Json.object
-    [ ("amount", Json.int amount)
-    , ("date", Json.string (DateFormat.isoDateString date))
-    ]
-    |> HttpUtils.jsonRequest "POST" "/income"
-    |> flip Task.andThen (HttpUtils.decodeHttpValue <| "id" := incomeIdDecoder)
+createIncome : Int -> Date -> (Result Error IncomeId -> msg) -> Cmd msg
+createIncome amount date handleResult =
+  let json =
+        Encode.object
+          [ ("amount", Encode.int amount)
+          , ("date", Encode.string (DateFormat.isoDateString date))
+          ]
+      expect = Http.expectJson (Decode.field "id" incomeIdDecoder)
+  in  HttpUtils.jsonRequest "POST" "/income" expect handleResult json
 
-editIncome : IncomeId -> Int -> Date -> Task Http.Error ()
-editIncome incomeId amount date =
-  Json.object
-    [ ("id", Json.int incomeId)
-    , ("amount", Json.int amount)
-    , ("date", Json.string (DateFormat.isoDateString date))
-    ]
-    |> HttpUtils.jsonRequest "PUT" "/income"
-    |> Task.map (always ())
+editIncome : IncomeId -> Int -> Date -> (Result Error String -> msg) -> Cmd msg
+editIncome incomeId amount date handleResult =
+  let json =
+        Encode.object
+          [ ("id", Encode.int incomeId)
+          , ("amount", Encode.int amount)
+          , ("date", Encode.string (DateFormat.isoDateString date))
+          ]
+  in  HttpUtils.jsonRequest "PUT" "/income" Http.expectString handleResult json
 
-deleteIncome : IncomeId -> Task Http.Error ()
+deleteIncome : IncomeId -> (Result Error String -> msg) -> Cmd msg
 deleteIncome incomeId =
-  HttpUtils.request "DELETE" ("/income?id=" ++ (toString incomeId))
-    |> Task.map (always ())
+  HttpUtils.request "DELETE" ("/income?id=" ++ (toString incomeId)) Http.expectString
 
-signOut : Task Http.Error ()
-signOut =
-  HttpUtils.request "POST" "/signOut"
-    |> Task.map (always ())
+createCategory : String -> String -> (Result Error CategoryId -> msg) -> Cmd msg
+createCategory name color handleResult =
+  let json =
+        Encode.object
+          [ ("name", Encode.string name)
+          , ("color", Encode.string color)
+          ]
+      expect = Http.expectJson (Decode.field "id" categoryIdDecoder)
+  in  HttpUtils.jsonRequest "POST" "/category" expect handleResult json
+
+editCategory : CategoryId -> String -> String -> (Result Error String -> msg) -> Cmd msg
+editCategory categoryId name color handleResult =
+  let json =
+        Encode.object
+          [ ("id", Encode.int categoryId)
+          , ("name", Encode.string name)
+          , ("color", Encode.string color)
+          ]
+  in  HttpUtils.jsonRequest "PUT" "/category" Http.expectString handleResult json
+
+deleteCategory : CategoryId -> (Result Error String -> msg) -> Cmd msg
+deleteCategory categoryId =
+  HttpUtils.request "DELETE" ("/category?id=" ++ (toString categoryId)) Http.expectString
+
+signOut : (Result Error String -> msg) -> Cmd msg
+signOut = HttpUtils.request "POST" "/signOut" Http.expectString
diff --git a/src/client/elm/SignIn/View.elm b/src/client/elm/SignIn/View.elm
index f23ca09..88f74b0 100644
--- a/src/client/elm/SignIn/View.elm
+++ b/src/client/elm/SignIn/View.elm
@@ -2,7 +2,7 @@ module SignIn.View exposing
   ( view
   )
 
-import Json.Decode as Json
+import Json.Decode as Decode
 
 import FontAwesome
 import View.Color as Color
@@ -30,7 +30,7 @@ view model signInModel =
         [ onSubmitPrevDefault (SignIn signInModel.login) ]
         [ input
             [ value signInModel.login
-            , on "input" (targetValue |> (Json.map <| (UpdateSignIn << SignInMsg.UpdateLogin)))
+            , on "input" (targetValue |> (Decode.map <| (UpdateSignIn << SignInMsg.UpdateLogin)))
             , name "email"
             ]
             []
diff --git a/src/client/elm/Update.elm b/src/client/elm/Update.elm
index e66414e..7006d5a 100644
--- a/src/client/elm/Update.elm
+++ b/src/client/elm/Update.elm
@@ -1,11 +1,10 @@
 module Update exposing
   ( update
-  , urlUpdate
   )
 
 import Task
 import Platform.Cmd exposing (Cmd)
-import Navigation
+import Navigation exposing (Location)
 
 import Page exposing (Page)
 
@@ -32,7 +31,6 @@ import Tooltip
 
 import Utils.Http exposing (errorKey)
 import Utils.Cmd exposing ((:>))
-import Utils.Tuple as Tuple
 
 update : Msg -> Model -> (Model, Cmd Msg)
 update msg model =
@@ -41,12 +39,15 @@ update msg model =
     NoOp ->
       (model, Cmd.none)
 
+    UpdatePage page ->
+      ({ model | page = page }, Cmd.none)
+
     SignIn email ->
       ( applySignIn model (SignInMsg.WaitingServer)
-      , Server.signIn email
-          |> Task.perform
-               (\error -> UpdateSignIn (SignInMsg.ErrorLogin (errorKey error)))
-               (\() -> UpdateSignIn SignInMsg.ValidLogin)
+      , Server.signIn email (\result -> case result of
+          Ok _ -> UpdateSignIn SignInMsg.ValidLogin
+          Err error -> UpdateSignIn (SignInMsg.ErrorLogin (errorKey error))
+        )
       )
 
     GoLoggedInView init ->
@@ -66,73 +67,100 @@ update msg model =
     UpdateLoggedIn loggedInMsg ->
       applyLoggedIn model loggedInMsg
 
-    CreatePayment name cost date frequency ->
+    SignOut ->
+      ( model
+      , Server.signOut (\result -> case result of
+          Ok _ -> GoSignInView
+          Err _ -> Error "SignOutError"
+        )
+      )
+
+    Error error ->
+      ({ model | errors = model.errors ++ [ error ] }, Cmd.none)
+
+    Dialog dialogMsg ->
+      Dialog.update DialogUpdate.update dialogMsg model.dialog.model model.dialog
+        |> Tuple.mapFirst (\dialog -> { model | dialog = dialog })
+        :> update (Tooltip Tooltip.HideMessage)
+
+    Tooltip tooltipMsg ->
+      let (newTooltip, command) = Tooltip.update tooltipMsg model.tooltip
+      in  ( { model | tooltip = newTooltip }
+          , Cmd.map Tooltip command
+          )
+
+    CreatePayment name cost date category frequency ->
       ( model
-      , Server.createPayment name cost date frequency
-          |> Task.perform
-               (always <| Error "CreatePaymentError")
-               (\paymentId -> UpdateLoggedIn <| LoggedInMsg.ValidateCreatePayment paymentId name cost date frequency)
+      , Server.createPayment name cost date category frequency (\result -> case result of
+          Ok paymentId -> UpdateLoggedIn <| LoggedInMsg.ValidateCreatePayment paymentId name cost date category frequency
+          Err _ -> Error "CreatePaymentError"
+        )
       )
 
-    EditPayment paymentId name cost date frequency ->
+    EditPayment paymentId name cost date category frequency ->
       ( model
-      , Server.editPayment paymentId name cost date frequency
-          |> Task.perform
-               (always <| Error "EditPaymentError")
-               (always <| UpdateLoggedIn <| LoggedInMsg.ValidateEditPayment paymentId name cost date frequency)
+      , Server.editPayment paymentId name cost date category frequency (\result -> case result of
+          Ok _ -> UpdateLoggedIn <| LoggedInMsg.ValidateEditPayment paymentId name cost date category frequency
+          Err _ -> Error "EditPaymentError"
+        )
       )
 
     DeletePayment paymentId ->
       ( model
-      , Server.deletePayment paymentId
-          |> Task.perform
-               (always <| Error "DeletePaymentError")
-               (always <| UpdateLoggedIn <| LoggedInMsg.ValidateDeletePayment paymentId)
+      , Server.deletePayment paymentId (\result -> case result of
+          Ok _ -> UpdateLoggedIn <| LoggedInMsg.ValidateDeletePayment paymentId
+          Err _ -> Error "DeletePaymentError"
+        )
       )
 
     CreateIncome amount date ->
       ( model
-      , Server.createIncome amount date
-          |> Task.perform
-               (always <| Error "CreateIncomeError")
-               (\incomeId -> UpdateLoggedIn <| LoggedInMsg.ValidateCreateIncome incomeId amount date)
+      , Server.createIncome amount date (\result -> case result of
+          Ok incomeId -> UpdateLoggedIn <| LoggedInMsg.ValidateCreateIncome incomeId amount date
+          Err _ -> Error "CreateIncomeError"
+        )
       )
 
     EditIncome incomeId amount date ->
       ( model
-      , Server.editIncome incomeId amount date
-          |> Task.perform
-               (always <| Error "EditIncomeError")
-               (always <| UpdateLoggedIn <| LoggedInMsg.ValidateEditIncome incomeId amount date)
+      , Server.editIncome incomeId amount date (\result -> case result of
+          Ok _ -> UpdateLoggedIn <| LoggedInMsg.ValidateEditIncome incomeId amount date
+          Err _ -> Error "EditIncomeError"
+        )
       )
 
     DeleteIncome incomeId ->
       ( model
-      , Server.deleteIncome incomeId
-          |> Task.perform
-               (always <| Error "DeleteIncomeError")
-               (always <| UpdateLoggedIn <| LoggedInMsg.ValidateDeleteIncome incomeId)
+      , Server.deleteIncome incomeId (\result -> case result of
+          Ok _ -> UpdateLoggedIn <| LoggedInMsg.ValidateDeleteIncome incomeId
+          Err _ -> Error "DeleteIncomeError"
+        )
       )
 
-    SignOut ->
+    CreateCategory name color ->
       ( model
-      , Server.signOut
-          |> Task.perform (always <| Error "SignOutError") (always GoSignInView)
+      , Server.createCategory name color (\result -> case result of
+          Ok categoryId -> UpdateLoggedIn <| LoggedInMsg.ValidateCreateCategory categoryId name color
+          Err _ -> Error "CreateCategoryError"
+        )
       )
 
-    Error error ->
-      ({ model | errors = model.errors ++ [ error ] }, Cmd.none)
+    EditCategory categoryId name color ->
+      ( model
+      , Server.editCategory categoryId name color (\result -> case result of
+          Ok _ -> UpdateLoggedIn <| LoggedInMsg.ValidateEditCategory categoryId name color
+          Err _ -> Error "EditCategoryError"
+        )
+      )
 
-    Dialog dialogMsg ->
-      Dialog.update DialogUpdate.update dialogMsg model.dialog.model model.dialog
-        |> Tuple.mapFst (\dialog -> { model | dialog = dialog })
-        :> update (Tooltip Tooltip.HideMessage)
+    DeleteCategory categoryId ->
+      ( model
+      , Server.deleteCategory categoryId (\result -> case result of
+          Ok _ -> UpdateLoggedIn <| LoggedInMsg.ValidateDeleteCategory categoryId
+          Err _ -> Error "DeleteCategoryError"
+        )
+      )
 
-    Tooltip tooltipMsg ->
-      let (newTooltip, command) = Tooltip.update tooltipMsg model.tooltip
-      in  ( { model | tooltip = newTooltip }
-          , Cmd.map Tooltip command
-          )
 
 applySignIn : Model -> SignInMsg.Msg -> Model
 applySignIn model signInMsg =
@@ -146,17 +174,9 @@ applyLoggedIn : Model -> LoggedInMsg.Msg -> (Model, Cmd Msg)
 applyLoggedIn model loggedInMsg =
   case model.view of
     V.LoggedInView loggedInView ->
-      let (loggedInView, cmd) = LoggedInUpdate.update model loggedInMsg loggedInView
-      in  ( { model | view = V.LoggedInView loggedInView }
+      let (view, cmd) = LoggedInUpdate.update model loggedInMsg loggedInView
+      in  ( { model | view = V.LoggedInView view }
           , Cmd.map UpdateLoggedIn cmd
           )
     _ ->
       (model, Cmd.none)
-
-urlUpdate : Result String Page -> Model -> (Model, Cmd Msg)
-urlUpdate result model =
-  case result of
-    Err _ ->
-      (model, Navigation.modifyUrl (Page.toHash model.page))
-    Ok page ->
-      ({ model | page = page }, Cmd.none)
diff --git a/src/client/elm/Utils/Cmd.elm b/src/client/elm/Utils/Cmd.elm
index 8b79446..5f41cbe 100644
--- a/src/client/elm/Utils/Cmd.elm
+++ b/src/client/elm/Utils/Cmd.elm
@@ -7,8 +7,8 @@ import Platform.Cmd as Cmd
 
 pipeUpdate : (model, Cmd msg) -> (model -> (model, Cmd msg)) -> (model, Cmd msg)
 pipeUpdate (model, cmd) f =
-  let (model', cmd') = f model
-  in  (model', Cmd.batch [ cmd, cmd' ])
+  let (newModel, newCmd) = f model
+  in  (newModel, Cmd.batch [ cmd, newCmd ])
 
 (:>) : (m, Cmd a) -> (m -> (m, Cmd a)) -> (m, Cmd a)
 (:>) = pipeUpdate
diff --git a/src/client/elm/Utils/Http.elm b/src/client/elm/Utils/Http.elm
index 4edc233..dd3870a 100644
--- a/src/client/elm/Utils/Http.elm
+++ b/src/client/elm/Utils/Http.elm
@@ -1,69 +1,39 @@
 module Utils.Http exposing
   ( jsonRequest
   , request
-  , requestWithBody
-  , decodeHttpValue
   , errorKey
   )
 
 import Http exposing (..)
 import Task exposing (..)
-import Json.Decode as JsonDecode exposing (Decoder)
-import Json.Encode as JsonEncode
-
-jsonRequest : String -> String -> JsonEncode.Value -> Task Error Value
-jsonRequest method url json =
-  json
-    |> JsonEncode.encode 0
-    |> Http.string
-    |> requestWithBody method url
-
-request : String -> String -> Task Error Value
-request method url = requestWithBody method url empty
-
-requestWithBody : String -> String -> Body -> Task Error Value
-requestWithBody method url body =
-  { verb = method
-  , headers = []
-  , url = url
-  , body = body
-  }
-    |> Http.send defaultSettings
-    |> mapError promoteError
-    |> flip Task.andThen handleResponse
-
-promoteError : RawError -> Error
-promoteError rawError =
-  case rawError of
-    RawTimeout -> Timeout
-    RawNetworkError -> NetworkError
-
-handleResponse : Response -> Task Error Value
-handleResponse response =
-  if 200 <= response.status && response.status < 300
-    then Task.succeed response.value
-    else fail (BadResponse response.status (responseString response.value))
-
-responseString : Value -> String
-responseString value =
-  case value of
-    Text str -> str
-    _ -> ""
-
-decodeHttpValue : Decoder a -> Value -> Task Error a
-decodeHttpValue decoder value =
-  case value of
-    Text str ->
-      case JsonDecode.decodeString decoder str of
-        Ok v -> succeed v
-        Err msg -> fail (UnexpectedPayload msg)
-    _ ->
-      fail (UnexpectedPayload "Response body is a blob, expecting a string.")
+import Json.Decode as Decode exposing (Decoder, Value)
+import Json.Encode as Encode
+
+jsonRequest : String -> String -> Expect a -> (Result Error a -> msg) -> Encode.Value -> Cmd msg
+jsonRequest method url expect handleResult value =
+  requestWithBody method url (jsonBody value) expect handleResult
+
+request : String -> String -> Expect a -> (Result Error a -> msg) -> Cmd msg
+request method url = requestWithBody method url emptyBody
+
+requestWithBody : String -> String -> Body -> Expect a -> (Result Error a -> msg) -> Cmd msg
+requestWithBody method url body expect handleResult =
+  let req = Http.request
+              { method = method
+              , headers = []
+              , url = url
+              , body = body
+              , expect = expect
+              , timeout = Nothing
+              , withCredentials = False
+              }
+  in  send handleResult req
 
 errorKey : Error -> String
 errorKey error =
   case error of
+    BadUrl _ -> "BadUrl"
     Timeout -> "Timeout"
     NetworkError -> "NetworkError"
-    UnexpectedPayload _ -> "UnexpectedPayload"
-    BadResponse _ key -> key
+    BadPayload _ _ -> "BadPayload"
+    BadStatus response -> response.body
diff --git a/src/client/elm/Utils/Json.elm b/src/client/elm/Utils/Json.elm
new file mode 100644
index 0000000..29e815b
--- /dev/null
+++ b/src/client/elm/Utils/Json.elm
@@ -0,0 +1,12 @@
+module Utils.Json exposing
+  ( dictDecoder
+  )
+
+import Json.Decode as Decode exposing (Decoder)
+import Dict exposing (Dict)
+
+dictDecoder : Decoder comparable -> Decoder a -> Decoder (Dict comparable a)
+dictDecoder keyDecoder valueDecoder =
+  Decode.map2 (,) keyDecoder valueDecoder
+    |> Decode.list
+    |> Decode.map Dict.fromList
diff --git a/src/client/elm/Utils/Maybe.elm b/src/client/elm/Utils/Maybe.elm
index 4a94aa5..46456e1 100644
--- a/src/client/elm/Utils/Maybe.elm
+++ b/src/client/elm/Utils/Maybe.elm
@@ -1,7 +1,8 @@
 module Utils.Maybe exposing
   ( isJust
-  , catMaybes
-  , maybeToList
+  , cat
+  , toList
+  , orElse
   )
 
 isJust : Maybe a -> Bool
@@ -10,8 +11,8 @@ isJust maybe =
     Just _  -> True
     Nothing -> False
 
-catMaybes : List (Maybe a) -> List a
-catMaybes =
+cat : List (Maybe a) -> List a
+cat =
   List.foldr
     (\mb xs ->
       case mb of
@@ -20,8 +21,14 @@ catMaybes =
     )
     []
 
-maybeToList : Maybe a -> List a
-maybeToList mb =
+toList : Maybe a -> List a
+toList mb =
   case mb of
     Just a  -> [a]
     Nothing -> []
+
+orElse : Maybe a -> Maybe a -> Maybe a
+orElse mb1 mb2 =
+  case mb1 of
+    Just x -> Just x
+    Nothing -> mb2
diff --git a/src/client/elm/Utils/Search.elm b/src/client/elm/Utils/Search.elm
new file mode 100644
index 0000000..1b70387
--- /dev/null
+++ b/src/client/elm/Utils/Search.elm
@@ -0,0 +1,10 @@
+module Utils.Search exposing
+  ( format
+  )
+
+import String
+
+import Utils.String as String
+
+format : String -> String
+format = String.unaccent << String.toLower
diff --git a/src/client/elm/Utils/String.elm b/src/client/elm/Utils/String.elm
new file mode 100644
index 0000000..90fe68e
--- /dev/null
+++ b/src/client/elm/Utils/String.elm
@@ -0,0 +1,38 @@
+module Utils.String exposing
+  ( unaccent
+  )
+
+unaccent : String -> String
+unaccent = String.map unaccentChar
+
+unaccentChar : Char -> Char
+unaccentChar c = case c of
+  'à' -> 'a'
+  'á' -> 'a'
+  'â' -> 'a'
+  'ã' -> 'a'
+  'ä' -> 'a'
+  'ç' -> 'c'
+  'è' -> 'e'
+  'é' -> 'e'
+  'ê' -> 'e'
+  'ë' -> 'e'
+  'ì' -> 'i'
+  'í' -> 'i'
+  'î' -> 'i'
+  'ï' -> 'i'
+  'ñ' -> 'n'
+  'ò' -> 'o'
+  'ó' -> 'o'
+  'ô' -> 'o'
+  'õ' -> 'o'
+  'ö' -> 'o'
+  'š' -> 's'
+  'ù' -> 'u'
+  'ú' -> 'u'
+  'û' -> 'u'
+  'ü' -> 'u'
+  'ý' -> 'y'
+  'ÿ' -> 'y'
+  'ž' -> 'z'
+  _ -> c
diff --git a/src/client/elm/Utils/Tuple.elm b/src/client/elm/Utils/Tuple.elm
deleted file mode 100644
index f9391a0..0000000
--- a/src/client/elm/Utils/Tuple.elm
+++ /dev/null
@@ -1,14 +0,0 @@
-module Utils.Tuple exposing
-  ( mapFst
-  , mapSnd
-  , mapBoth
-  )
-
-mapFst : (a -> x) -> (a, b) -> (x, b)
-mapFst f (a, b) = (f a, b)
-
-mapSnd : (b -> x) -> (a, b) -> (a, x)
-mapSnd f (a, b) = (a, f b)
-
-mapBoth : (a -> x) -> (b -> y) -> (a, b) -> (x, y)
-mapBoth f g (a, b) = (f a, g b)
diff --git a/src/client/elm/Validation.elm b/src/client/elm/Validation.elm
index 1729daa..18b3934 100644
--- a/src/client/elm/Validation.elm
+++ b/src/client/elm/Validation.elm
@@ -1,14 +1,18 @@
 module Validation exposing
   ( date
+  , category
   )
 
-import String exposing (toInt, split)
 import Date exposing (Date)
-import Date.Extra.Create exposing (dateFromFields)
 import Date.Extra.Core exposing (intToMonth)
+import Date.Extra.Create exposing (dateFromFields)
+import Dict
+import String exposing (toInt, split)
 
 import Form.Validate as Validate exposing (..)
 
+import Model.Category exposing (Categories, CategoryId)
+
 date : Validation String Date
 date =
   customValidation string (\str ->
@@ -20,3 +24,15 @@ date =
           _ -> Err (customError "InvalidDate")
       _ -> Err (customError "InvalidDate")
   )
+
+category : Categories -> Validation String CategoryId
+category categories =
+  customValidation string (\str ->
+    case toInt str of
+      Ok category ->
+        if List.member category (Dict.keys categories)
+          then Ok category
+          else Err (customError "InvalidCategory")
+      Err _ ->
+        Err (customError "InvalidCategory")
+  )
diff --git a/src/client/elm/View.elm b/src/client/elm/View.elm
index 4a0822f..66c498a 100644
--- a/src/client/elm/View.elm
+++ b/src/client/elm/View.elm
@@ -3,7 +3,6 @@ module View exposing
   )
 
 import Html exposing (..)
-import Html.App as Html
 import Html.Attributes exposing (..)
 
 import Model exposing (Model)
diff --git a/src/client/elm/View/Events.elm b/src/client/elm/View/Events.elm
index c50fe98..d71d67d 100644
--- a/src/client/elm/View/Events.elm
+++ b/src/client/elm/View/Events.elm
@@ -2,7 +2,7 @@ module View.Events exposing
   ( onSubmitPrevDefault
   )
 
-import Json.Decode as Json
+import Json.Decode as Decode
 import Html exposing (..)
 import Html.Events exposing (..)
 import Html.Attributes exposing (..)
@@ -12,4 +12,4 @@ onSubmitPrevDefault value =
   onWithOptions
     "submit"
     { defaultOptions | preventDefault = True }
-    (Json.succeed value)
+    (Decode.succeed value)
diff --git a/src/client/elm/View/Form.elm b/src/client/elm/View/Form.elm
index dcde47d..7a4965d 100644
--- a/src/client/elm/View/Form.elm
+++ b/src/client/elm/View/Form.elm
@@ -1,5 +1,7 @@
 module View.Form exposing
   ( textInput
+  , colorInput
+  , selectInput
   , radioInputs
   , hiddenSubmit
   )
@@ -13,7 +15,7 @@ import View.Color as Color
 
 import Form exposing (Form, FieldState)
 import Form.Input as Input
-import Form.Error as FormError exposing (Error(..))
+import Form.Error as FormError exposing (ErrorValue(..))
 import Form.Field as Field
 
 import Msg exposing (Msg)
@@ -27,6 +29,7 @@ import Utils.Maybe exposing (isJust)
 textInput : Translations -> Form String a -> String -> String -> Html Form.Msg
 textInput translations form formName fieldName =
   let field = Form.getFieldAsString fieldName form
+      fieldId = formName ++ fieldName
   in  div
         [ classList
             [ ("textInput", True)
@@ -35,21 +38,39 @@ textInput translations form formName fieldName =
         ]
         [ Input.textInput
             field
-            [ id (formName ++ fieldName)
+            [ id fieldId
             , classList [ ("filled", isJust field.value) ]
+            , value (Maybe.withDefault "" field.value)
             ]
         , label
-            [ for (formName ++ fieldName) ]
-            [ text (Translations.getMessage translations (formName ++ fieldName)) ]
+            [ for fieldId ]
+            [ text (Translations.getMessage translations fieldId) ]
         , button
-            [ type' "button"
-            , onClick (Form.Input fieldName Field.EmptyField)
+            [ type_ "button"
+            , onClick (Form.Input fieldName Form.Text Field.EmptyField)
             , tabindex -1
             ]
             [ FontAwesome.times Color.silver 15 ]
-        , case field.liveError of
-            Just error -> formError translations error
-            Nothing -> text ""
+        , formError translations field
+        ]
+
+colorInput : Translations -> Form String a -> String -> String -> Html Form.Msg
+colorInput translations form formName fieldName =
+  let field = Form.getFieldAsString fieldName form
+  in  div
+        [ classList
+            [ ("colorInput", True)
+            , ("error", isJust field.liveError)
+            ]
+        ]
+        [ label
+            [ for (formName ++ fieldName) ]
+            [ text (Translations.getMessage translations (formName ++ fieldName)) ]
+        , Input.textInput
+            field
+            [ id (formName ++ fieldName)
+            , type_ "color"
+            ]
         ]
 
 radioInputs : Translations -> Form String a -> String -> String -> List String -> Html Form.Msg
@@ -67,9 +88,7 @@ radioInputs translations form formName radioName fieldNames =
         , div
             [ class "radioInputs" ]
             (List.map (radioInput translations field formName) fieldNames)
-        , case field.liveError of
-            Just error -> formError translations error
-            Nothing -> text ""
+        , formError translations field
         ]
 
 radioInput : Translations -> FieldState String String -> String -> String -> Html Form.Msg
@@ -89,17 +108,41 @@ radioInput translations field formName fieldName =
         ]
     ]
 
-formError : Translations -> FormError.Error String -> Html msg
-formError translations error =
-  let errorElement error params =
-        div
-          [ class "errorMessage" ]
-          [ text (Translations.getParamMessage params translations error) ]
-  in  case error of
-        CustomError key -> errorElement key []
-        SmallerIntThan n -> errorElement "SmallerIntThan" [toString n]
-        GreaterIntThan n -> errorElement "GreaterIntThan" [toString n]
-        error -> errorElement (toString error) []
+selectInput : Translations -> Form String a -> String -> String -> List (String, String) -> Html Form.Msg
+selectInput translations form formName selectName options =
+  let field = Form.getFieldAsString selectName form
+      fieldId = formName ++ selectName
+  in  div
+        [ classList
+            [ ("selectInput", True)
+            , ("error", isJust field.liveError)
+            ]
+        ]
+        [ label
+            [ for fieldId ]
+            [ text (Translations.getMessage translations fieldId) ]
+        , Input.selectInput
+            (("", "") :: options)
+            field
+            [ id fieldId ]
+        , formError translations field
+        ]
+
+formError : Translations -> FieldState String a -> Html msg
+formError translations field =
+  case field.liveError of
+    Just error ->
+      let errorElement error params =
+            div
+              [ class "errorMessage" ]
+              [ text (Translations.getParamMessage params translations error) ]
+      in  case error of
+            CustomError key -> errorElement key []
+            SmallerIntThan n -> errorElement "SmallerIntThan" [toString n]
+            GreaterIntThan n -> errorElement "GreaterIntThan" [toString n]
+            error -> errorElement (toString error) []
+    Nothing ->
+      text ""
 
 hiddenSubmit : msg -> Html msg
 hiddenSubmit msg =
diff --git a/src/client/elm/View/Header.elm b/src/client/elm/View/Header.elm
index 08a429f..12fb87c 100644
--- a/src/client/elm/View/Header.elm
+++ b/src/client/elm/View/Header.elm
@@ -37,6 +37,7 @@ view model =
              LoggedInView { me, users } ->
                [ item Home "PaymentsTitle"
                , item Income "Income"
+               , item Categories "Categories"
                , item Statistics "Statistics"
                , div
                    [ class "nameSignOut" ]
diff --git a/src/server/Controller/Category.hs b/src/server/Controller/Category.hs
new file mode 100644
index 0000000..19109a3
--- /dev/null
+++ b/src/server/Controller/Category.hs
@@ -0,0 +1,54 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+module Controller.Category
+  ( create
+  , edit
+  , delete
+  ) where
+
+import Control.Monad.IO.Class (liftIO)
+
+import Data.Text (Text)
+import Network.HTTP.Types.Status (ok200, badRequest400)
+import qualified Data.Text.Lazy as TL
+import Web.Scotty hiding (delete)
+
+import Json (jsonId)
+import Model.Database
+import qualified Model.Category as Category
+import qualified Model.Json.CreateCategory as Json
+import qualified Model.Json.EditCategory as Json
+import qualified Model.Message.Key as Key
+import qualified Model.PaymentCategory as PaymentCategory
+import qualified Secure
+
+create :: Json.CreateCategory -> ActionM ()
+create (Json.CreateCategory name color) =
+  Secure.loggedAction (\_ ->
+    (liftIO . runDb $ Category.create name color) >>= jsonId
+  )
+
+edit :: Json.EditCategory -> ActionM ()
+edit (Json.EditCategory categoryId name color) =
+  Secure.loggedAction (\_ -> do
+    updated <- liftIO . runDb $ Category.edit categoryId name color
+    if updated
+      then status ok200
+      else status badRequest400
+  )
+
+delete :: Text -> ActionM ()
+delete categoryId =
+  Secure.loggedAction (\_ -> do
+    deleted <- liftIO . runDb $ do
+      paymentCategories <- PaymentCategory.listByCategory (textToKey categoryId)
+      if null paymentCategories
+        then Category.delete (textToKey categoryId)
+        else return False
+    if deleted
+      then
+        status ok200
+      else do
+        status badRequest400
+        text . TL.pack . show $ Key.CategoryNotDeleted
+  )
diff --git a/src/server/Controller/Index.hs b/src/server/Controller/Index.hs
index abb3b17..96d0a49 100644
--- a/src/server/Controller/Index.hs
+++ b/src/server/Controller/Index.hs
@@ -1,18 +1,18 @@
 module Controller.Index
-  ( getIndex
+  ( get
   , signOut
   ) where
 
 import Control.Monad.IO.Class (liftIO)
 
-import Web.Scotty
+import Web.Scotty hiding (get)
 
 import Network.HTTP.Types.Status (ok200)
 
 import Data.Text (Text)
 import Data.Time.Clock (getCurrentTime, diffUTCTime)
 
-import Database.Persist hiding (Key)
+import Database.Persist hiding (Key, get)
 
 import Conf (Conf(..))
 import qualified LoginSession
@@ -28,8 +28,8 @@ import Model.Init (getInit)
 
 import View.Page (page)
 
-getIndex :: Conf -> Maybe Text -> ActionM ()
-getIndex conf mbToken = do
+get :: Conf -> Maybe Text -> ActionM ()
+get conf mbToken = do
   initResult <- case mbToken of
     Just token -> do
       userOrError <- validateSignIn conf token
diff --git a/src/server/Controller/Payment.hs b/src/server/Controller/Payment.hs
index 9155a78..e3f1082 100644
--- a/src/server/Controller/Payment.hs
+++ b/src/server/Controller/Payment.hs
@@ -23,6 +23,7 @@ import Json (jsonId)
 
 import Model.Database
 import qualified Model.Payment as Payment
+import qualified Model.PaymentCategory as PaymentCategory
 import qualified Model.Json.CreatePayment as Json
 import qualified Model.Json.EditPayment as Json
 
@@ -33,15 +34,27 @@ list =
   )
 
 create :: Json.CreatePayment -> ActionM ()
-create (Json.CreatePayment name cost date frequency) =
+create (Json.CreatePayment name cost date category frequency) =
   Secure.loggedAction (\user ->
-    (liftIO . runDb $ Payment.create (entityKey user) name cost date frequency) >>= jsonId
+    (liftIO . runDb $ do
+      PaymentCategory.set name category
+      Payment.create (entityKey user) name cost date frequency
+    ) >>= jsonId
   )
 
 editOwn :: Json.EditPayment -> ActionM ()
-editOwn (Json.EditPayment paymentId name cost date frequency) =
+editOwn (Json.EditPayment paymentId name cost date category frequency) =
   Secure.loggedAction (\user -> do
-    updated <- liftIO . runDb $ Payment.editOwn (entityKey user) paymentId name cost date frequency
+    updated <- liftIO . runDb $ do
+      mbPayment <- fmap entityVal <$> Payment.find paymentId
+      case mbPayment of
+        Just payment -> do
+          edited <- Payment.editOwn (entityKey user) paymentId name cost date frequency
+          if edited
+            then PaymentCategory.edit (paymentName payment) name category >> return True
+            else return edited
+        _ ->
+          return False
     if updated
       then status ok200
       else status badRequest400
diff --git a/src/server/Controller/User.hs b/src/server/Controller/User.hs
index 1baab18..d8604ac 100644
--- a/src/server/Controller/User.hs
+++ b/src/server/Controller/User.hs
@@ -2,7 +2,6 @@
 
 module Controller.User
   ( getUsers
-  , whoAmI
   ) where
 
 import Web.Scotty
@@ -12,16 +11,10 @@ import Control.Monad.IO.Class (liftIO)
 import qualified Secure
 
 import Model.Database
-import qualified Model.User as U
+import qualified Model.User as User
 
 getUsers :: ActionM ()
 getUsers =
   Secure.loggedAction (\_ ->
-    (liftIO $ map U.getJsonUser <$> runDb U.getUsers) >>= json
-  )
-
-whoAmI :: ActionM ()
-whoAmI =
-  Secure.loggedAction (\user ->
-    json (U.getJsonUser user)
+    (liftIO $ map User.getJsonUser <$> runDb User.list) >>= json
   )
diff --git a/src/server/Design/Constants.hs b/src/server/Design/Constants.hs
index a532ac8..4e2b8cc 100644
--- a/src/server/Design/Constants.hs
+++ b/src/server/Design/Constants.hs
@@ -2,13 +2,13 @@ module Design.Constants where
 
 import Clay
 
-iconFontSize :: Size Abs
+iconFontSize :: Size LengthUnit
 iconFontSize = px 32
 
-radius :: Size Abs
+radius :: Size LengthUnit
 radius = px 3
 
-blockPadding :: Size Abs
+blockPadding :: Size LengthUnit
 blockPadding = px 15
 
 blockPercentWidth :: Double
diff --git a/src/server/Design/Dialog.hs b/src/server/Design/Dialog.hs
index 2320c45..4678633 100644
--- a/src/server/Design/Dialog.hs
+++ b/src/server/Design/Dialog.hs
@@ -14,8 +14,11 @@ design = do
   ".content" ? do
     minWidth (px 270)
 
-  ".paymentDialog" ? do
-    ".radioGroup" ? ".title" ? display none
+    ".paymentDialog" & do
+      ".radioGroup" ? ".title" ? display none
+      ".selectInput" ? do
+        select ? width (pct 100)
+        marginBottom (em 1)
 
   ".deletePaymentDialog" <> ".deleteIncomeDialog" ? do
     h1 ? marginBottom (em 1.5)
diff --git a/src/server/Design/Form.hs b/src/server/Design/Form.hs
index 3043125..ebb8ac8 100644
--- a/src/server/Design/Form.hs
+++ b/src/server/Design/Form.hs
@@ -18,6 +18,10 @@ design = do
   let inputPaddingBottom = 3
   let inputZIndex = 1
 
+  label ? do
+    cursor pointer
+    color Color.silver
+
   ".textInput" ? do
     position relative
     marginBottom (em 1.5)
@@ -44,7 +48,6 @@ design = do
       position absolute
       top (px inputTop)
       left (px 0)
-      color Color.silver
       transition "all" (sec 0.2) easeIn (sec 0)
 
     button ? do
@@ -68,6 +71,15 @@ design = do
         color Color.chestnutRose
         fontSize (pct 80)
 
+  ".colorInput" ? do
+    display flex
+    alignItems center
+    marginBottom (em 1.5)
+
+    input ? do
+      borderColor transparent
+      backgroundColor transparent
+
   ".radioGroup" ? do
     position relative
     marginBottom (em 2)
@@ -90,11 +102,29 @@ design = do
         width (px 30)
         margin (px 0) (px (-15)) (px 0) (px (-15))
 
-      label ? cursor pointer
-
       "input:focus + label" ? do
         textDecoration underline
 
       "input:checked + label" ? do
         color Color.chestnutRose
         fontWeight bold
+
+  ".selectInput" ? do
+    label ? do
+      display block
+      marginBottom (px 10)
+      fontSize (pct 80)
+    select ? do
+      backgroundColor Color.white
+      border solid (px 1) Color.silver
+      sym borderRadius (px 3)
+      sym2 padding (px 5) (px 8)
+      option ? do
+        firstChild & display none
+        sym2 padding (px 5) (px 8)
+    ".error" & do
+      select ? borderColor Color.chestnutRose
+      ".errorMessage" ? do
+        color Color.chestnutRose
+        fontSize (pct 80)
+        marginTop (em 0.5)
diff --git a/src/server/Design/Helper.hs b/src/server/Design/Helper.hs
index f25cf05..869616d 100644
--- a/src/server/Design/Helper.hs
+++ b/src/server/Design/Helper.hs
@@ -17,13 +17,12 @@ import Data.Monoid ((<>))
 
 import Design.Constants
 import Design.Color as Color
-import qualified Clay.Display as D
 
 clearFix :: Css
 clearFix =
   after & do
     content (stringContent "")
-    display D.table
+    display displayTable
     clear both
 
 button :: Color -> Color -> Size a -> (Color -> Color) -> Css
@@ -40,7 +39,7 @@ button backgroundCol textCol h focusOp = do
   hover & backgroundColor (focusOp backgroundCol)
   focus & backgroundColor (focusOp backgroundCol)
 
-iconButton :: Color -> Color -> Size Abs -> (Color -> Color) -> Css
+iconButton :: Color -> Color -> Size LengthUnit -> (Color -> Color) -> Css
 iconButton backgroundCol textCol h focusOp = do
   button backgroundCol textCol h focusOp
   i <> span ? do
diff --git a/src/server/Design/LoggedIn.hs b/src/server/Design/LoggedIn.hs
index 2899fa4..4a21832 100644
--- a/src/server/Design/LoggedIn.hs
+++ b/src/server/Design/LoggedIn.hs
@@ -7,16 +7,39 @@ module Design.LoggedIn
 import Clay
 
 import qualified Design.LoggedIn.Home as Home
-import qualified Design.LoggedIn.Income as Income
 import qualified Design.LoggedIn.Stat as Stat
 import qualified Design.LoggedIn.Table as Table
 
+import qualified Design.Helper as Helper
+import qualified Design.Constants as Constants
+import qualified Design.Color as Color
+import qualified Design.Media as Media
+
 design :: Css
 design = do
   ".home" ? Home.design
-  ".income" ? Income.design
   ".stat" ? Stat.design
   Table.design
 
-  ".textual" ? do
+  ".withMargin" ? do
     "margin" -: "0 2vw"
+
+  ".titleButton" ? do
+    h1 ? do
+      Media.tabletDesktop $ float floatLeft
+
+    button ? do
+      Helper.button Color.chestnutRose Color.white (px Constants.inputHeight) Constants.focusLighten
+      Media.tabletDesktop $ do
+        float floatRight
+        position relative
+        top (px (-8))
+      Media.mobile $ do
+        width (pct 100)
+        marginBottom (px 20)
+
+  ".tag" ? do
+    sym borderRadius (px 4)
+    sym2 padding (px 2) (px 5)
+    boxShadow (px 2) (px 2) (px 5) (rgba 0 0 0 0.3)
+    color Color.white
diff --git a/src/server/Design/LoggedIn/Home/Table.hs b/src/server/Design/LoggedIn/Home/Table.hs
index 73ced3a..cb46ac9 100644
--- a/src/server/Design/LoggedIn/Home/Table.hs
+++ b/src/server/Design/LoggedIn/Home/Table.hs
@@ -11,17 +11,20 @@ import qualified Design.Media as Media
 design :: Css
 design = do
   ".cell" ? do
-    ".category" & do
-      Media.tabletDesktop $ width (pct 36)
+    ".name" & do
+      Media.tabletDesktop $ width (pct 30)
 
     ".cost" & do
-      Media.tabletDesktop $ width (pct 15)
+      Media.tabletDesktop $ width (pct 10)
 
     ".user" & do
-      Media.tabletDesktop $ width (pct 20)
+      Media.tabletDesktop $ width (pct 15)
+
+    ".category" & do
+      Media.tabletDesktop $ width (pct 10)
 
     ".date" & do
-      Media.tabletDesktop $ width (pct 20)
+      Media.tabletDesktop $ width (pct 15)
       Media.desktop $ do
         ".shortDate" ? display none
         ".longDate" ? display inline
diff --git a/src/server/Design/LoggedIn/Income.hs b/src/server/Design/LoggedIn/Income.hs
deleted file mode 100644
index c44c67b..0000000
--- a/src/server/Design/LoggedIn/Income.hs
+++ /dev/null
@@ -1,29 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-
-module Design.LoggedIn.Income
-  ( design
-  ) where
-
-import Clay
-
-import qualified Design.Helper as Helper
-import qualified Design.Constants as Constants
-import qualified Design.Color as Color
-import qualified Design.Media as Media
-
-design :: Css
-design =
-  ".monthlyNetIncomes" ? do
-
-    h1 ? do
-      Media.tabletDesktop $ float floatLeft
-
-    ".addIncome" ? do
-      Helper.button Color.chestnutRose Color.white (px Constants.inputHeight) Constants.focusLighten
-      Media.tabletDesktop $ do
-        float floatRight
-        position relative
-        top (px (-8))
-      Media.mobile $ do
-        width (pct 100)
-        marginBottom (px 20)
diff --git a/src/server/Design/LoggedIn/Table.hs b/src/server/Design/LoggedIn/Table.hs
index 1af5e2b..44b001a 100644
--- a/src/server/Design/LoggedIn/Table.hs
+++ b/src/server/Design/LoggedIn/Table.hs
@@ -7,7 +7,6 @@ module Design.LoggedIn.Table
 import Data.Monoid ((<>))
 
 import Clay
-import qualified Clay.Display as D
 
 import Design.Color as Color
 import qualified Design.Media as Media
@@ -19,7 +18,7 @@ design = do
     textAlign (alignSide sideCenter)
 
   ".lines" ? do
-    Media.tabletDesktop $ display D.table
+    Media.tabletDesktop $ display displayTable
     width (pct 100)
     textAlign (alignSide (sideCenter))
 
diff --git a/src/server/Design/Media.hs b/src/server/Design/Media.hs
index d61a8e1..77220ee 100644
--- a/src/server/Design/Media.hs
+++ b/src/server/Design/Media.hs
@@ -29,8 +29,8 @@ desktop = query [Media.minWidth tabletDesktopLimit]
 query :: [Feature] -> Css -> Css
 query = Clay.query Media.screen
 
-mobileTabletLimit :: Size Abs
+mobileTabletLimit :: Size LengthUnit
 mobileTabletLimit = (px 520)
 
-tabletDesktopLimit :: Size Abs
+tabletDesktopLimit :: Size LengthUnit
 tabletDesktopLimit = (px 950)
diff --git a/src/server/Job/WeeklyReport.hs b/src/server/Job/WeeklyReport.hs
index 0d1eb35..5cde3e9 100644
--- a/src/server/Job/WeeklyReport.hs
+++ b/src/server/Job/WeeklyReport.hs
@@ -7,7 +7,7 @@ import Data.Time.Clock (UTCTime, getCurrentTime)
 import Model.Database (runDb)
 import qualified Model.Payment as Payment
 import qualified Model.Income as Income
-import Model.User (getUsers)
+import qualified Model.User as User
 
 import SendMail
 
@@ -25,7 +25,7 @@ weeklyReport conf mbLastExecution = do
         (,,) <$>
           Payment.modifiedDuring lastExecution now <*>
           Income.modifiedDuring lastExecution now <*>
-          getUsers
+          User.list
       _ <- sendMail (mail conf users payments incomes lastExecution now)
       return ()
   return now
diff --git a/src/server/Main.hs b/src/server/Main.hs
index 2ce8115..b7764c9 100644
--- a/src/server/Main.hs
+++ b/src/server/Main.hs
@@ -8,10 +8,11 @@ import Job.Daemon (runDaemons)
 
 import qualified Data.Text.Lazy as LT
 
-import Controller.Index
-import Controller.SignIn
-import Controller.Payment as Payment
-import Controller.Income as Income
+import qualified Controller.Index as Index
+import qualified Controller.SignIn as SignIn
+import qualified Controller.Payment as Payment
+import qualified Controller.Income as Income
+import qualified Controller.Category as Category
 
 import Model.Database (runMigrations)
 
@@ -27,14 +28,14 @@ main = do
 
     get "/" $ do
       signInToken <- mbParam "signInToken"
-      getIndex conf signInToken
+      Index.get conf signInToken
 
     post "/signIn" $ do
       email <- param "email"
-      signIn conf email
+      SignIn.signIn conf email
 
     post "/signOut" $
-      signOut conf
+      Index.signOut conf
 
     post "/payment" $
       jsonData >>= Payment.create
@@ -56,5 +57,15 @@ main = do
       incomeId <- param "id"
       Income.deleteOwn incomeId
 
+    post "/category" $
+      jsonData >>= Category.create
+
+    put "/category" $
+      jsonData >>= Category.edit
+
+    delete "/category" $ do
+      categoryId <- param "id"
+      Category.delete categoryId
+
 mbParam :: Parsable a => LT.Text -> ActionM (Maybe a)
 mbParam key = (Just <$> param key) `rescue` (const . return $ Nothing)
diff --git a/src/server/Model/Category.hs b/src/server/Model/Category.hs
new file mode 100644
index 0000000..50c3622
--- /dev/null
+++ b/src/server/Model/Category.hs
@@ -0,0 +1,56 @@
+module Model.Category
+  ( list
+  , create
+  , edit
+  , delete
+  ) where
+
+import Data.Text (Text)
+import Data.Maybe (isJust)
+import Data.Time.Clock (getCurrentTime)
+
+import Control.Monad.IO.Class (liftIO)
+
+import Database.Persist hiding (delete)
+
+import Model.Database
+import qualified Model.Json.Category as Json
+
+list :: Persist [Json.Category]
+list = map getJsonCategory <$> selectList [ CategoryDeletedAt ==. Nothing ] []
+
+getJsonCategory :: Entity Category -> Json.Category
+getJsonCategory categoryEntity =
+  Json.Category (entityKey categoryEntity) (categoryName category) (categoryColor category)
+  where category = entityVal categoryEntity
+
+create :: Text -> Text -> Persist CategoryId
+create name color = do
+  now <- liftIO getCurrentTime
+  insert (Category name color now Nothing Nothing)
+
+edit :: CategoryId -> Text -> Text -> Persist Bool
+edit categoryId name color = do
+  mbCategory <- get categoryId
+  if isJust mbCategory
+    then do
+      now <- liftIO getCurrentTime
+      update categoryId
+        [ CategoryEditedAt =. Just now
+        , CategoryName =. name
+        , CategoryColor =. color
+        ]
+      return True
+    else
+      return False
+
+delete :: CategoryId -> Persist Bool
+delete categoryId = do
+  mbCategory <- get categoryId
+  if isJust mbCategory
+    then do
+      now <- liftIO getCurrentTime
+      update categoryId [CategoryDeletedAt =. Just now]
+      return True
+    else
+      return False
diff --git a/src/server/Model/Database.hs b/src/server/Model/Database.hs
index 7f8326e..ba302de 100644
--- a/src/server/Model/Database.hs
+++ b/src/server/Model/Database.hs
@@ -46,6 +46,20 @@ Payment
   editedAt UTCTime Maybe
   deletedAt UTCTime Maybe
   deriving Show
+Category
+  name Text
+  color Text
+  createdAt UTCTime
+  editedAt UTCTime Maybe
+  deletedAt UTCTime Maybe
+  deriving Show
+PaymentCategory
+  name Text
+  category CategoryId
+  createdAt UTCTime
+  editedAt UTCTime Maybe
+  UniqPaymentCategoryName name
+  deriving Show
 SignIn
   token Text
   creation UTCTime
diff --git a/src/server/Model/Income.hs b/src/server/Model/Income.hs
index b7dd11c..ff6accd 100644
--- a/src/server/Model/Income.hs
+++ b/src/server/Model/Income.hs
@@ -1,6 +1,5 @@
 module Model.Income
-  ( getJsonIncome
-  , getIncomes
+  ( list
   , create
   , editOwn
   , deleteOwn
@@ -17,14 +16,14 @@ import Database.Persist
 import Model.Database
 import qualified Model.Json.Income as Json
 
+list :: Persist [Json.Income]
+list = map getJsonIncome <$> selectList [IncomeDeletedAt ==. Nothing] []
+
 getJsonIncome :: Entity Income -> Json.Income
 getJsonIncome incomeEntity =
   Json.Income (entityKey incomeEntity) (incomeUserId income) (incomeDate income) (incomeAmount income)
   where income = entityVal incomeEntity
 
-getIncomes :: Persist [Entity Income]
-getIncomes = selectList [IncomeDeletedAt ==. Nothing] []
-
 create :: UserId -> Day -> Int -> Persist IncomeId
 create userId date amount = do
   now <- liftIO getCurrentTime
diff --git a/src/server/Model/Init.hs b/src/server/Model/Init.hs
index 09ac627..7610b25 100644
--- a/src/server/Model/Init.hs
+++ b/src/server/Model/Init.hs
@@ -10,22 +10,21 @@ import Database.Persist
 
 import Model.Database
 
-import Model.Json.Init (Init, Init(Init))
+import Model.Json.Init (Init)
 import qualified Model.Payment as Payment
-import Model.User (getUsers, getJsonUser)
-import Model.Income (getIncomes, getJsonIncome)
+import qualified Model.User as User
+import qualified Model.Income as Income
+import qualified Model.Category as Category
+import qualified Model.PaymentCategory as PaymentCategory
 
 import qualified Model.Json.Init as Init
 
 getInit :: Entity User -> Persist Init
 getInit user =
-  liftIO . runDb $ do
-    users <- getUsers
-    payments <- Payment.list
-    incomes <- getIncomes
-    return $ Init
-      { Init.users = map getJsonUser users
-      , Init.me = entityKey user
-      , Init.payments = payments
-      , Init.incomes = map getJsonIncome incomes
-      }
+  liftIO . runDb $ Init.Init <$>
+    (map User.getJson <$> User.list) <*>
+    (return . entityKey $ user) <*>
+    Payment.list <*>
+    Income.list <*>
+    Category.list <*>
+    PaymentCategory.list
diff --git a/src/server/Model/Json/Category.hs b/src/server/Model/Json/Category.hs
new file mode 100644
index 0000000..daad4c2
--- /dev/null
+++ b/src/server/Model/Json/Category.hs
@@ -0,0 +1,20 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Model.Json.Category
+  ( Category(..)
+  ) where
+
+import GHC.Generics
+
+import Data.Aeson
+import Data.Text (Text)
+
+import Model.Database (CategoryId)
+
+data Category = Category
+  { id :: CategoryId
+  , name :: Text
+  , color :: Text
+  } deriving (Show, Generic)
+
+instance ToJSON Category
diff --git a/src/server/Model/Json/CreateCategory.hs b/src/server/Model/Json/CreateCategory.hs
new file mode 100644
index 0000000..fffc882
--- /dev/null
+++ b/src/server/Model/Json/CreateCategory.hs
@@ -0,0 +1,17 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Model.Json.CreateCategory
+  ( CreateCategory(..)
+  ) where
+
+import GHC.Generics
+
+import Data.Aeson
+import Data.Text (Text)
+
+data CreateCategory = CreateCategory
+  { name :: Text
+  , color :: Text
+  } deriving (Show, Generic)
+
+instance FromJSON CreateCategory
diff --git a/src/server/Model/Json/CreatePayment.hs b/src/server/Model/Json/CreatePayment.hs
index 4ba9e1a..5bc6b47 100644
--- a/src/server/Model/Json/CreatePayment.hs
+++ b/src/server/Model/Json/CreatePayment.hs
@@ -10,12 +10,14 @@ import Data.Aeson
 import Data.Time.Calendar (Day)
 import Data.Text (Text)
 
+import Model.Database (CategoryId)
 import Model.Frequency (Frequency)
 
 data CreatePayment = CreatePayment
   { name :: Text
   , cost :: Int
   , date :: Day
+  , category :: CategoryId
   , frequency :: Frequency
   } deriving (Show, Generic)
 
diff --git a/src/server/Model/Json/EditCategory.hs b/src/server/Model/Json/EditCategory.hs
new file mode 100644
index 0000000..bda3418
--- /dev/null
+++ b/src/server/Model/Json/EditCategory.hs
@@ -0,0 +1,20 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Model.Json.EditCategory
+  ( EditCategory(..)
+  ) where
+
+import GHC.Generics
+
+import Data.Aeson
+import Data.Text (Text)
+
+import Model.Database (CategoryId)
+
+data EditCategory = EditCategory
+  { id :: CategoryId
+  , name :: Text
+  , color :: Text
+  } deriving (Show, Generic)
+
+instance FromJSON EditCategory
diff --git a/src/server/Model/Json/EditPayment.hs b/src/server/Model/Json/EditPayment.hs
index 4e91000..35f44e5 100644
--- a/src/server/Model/Json/EditPayment.hs
+++ b/src/server/Model/Json/EditPayment.hs
@@ -11,13 +11,14 @@ import Data.Time.Calendar (Day)
 import Data.Text (Text)
 
 import Model.Frequency (Frequency)
-import Model.Database (PaymentId)
+import Model.Database (PaymentId, CategoryId)
 
 data EditPayment = EditPayment
   { id :: PaymentId
   , name :: Text
   , cost :: Int
   , date :: Day
+  , category :: CategoryId
   , frequency :: Frequency
   } deriving (Show, Generic)
 
diff --git a/src/server/Model/Json/Init.hs b/src/server/Model/Json/Init.hs
index 5e6d2a2..b9f7f40 100644
--- a/src/server/Model/Json/Init.hs
+++ b/src/server/Model/Json/Init.hs
@@ -13,6 +13,8 @@ import Model.Database (UserId)
 import Model.Json.User (User)
 import Model.Json.Payment (Payment)
 import Model.Json.Income (Income)
+import Model.Json.Category (Category)
+import Model.Json.PaymentCategory (PaymentCategory)
 import Model.Message.Key (Key)
 
 data Init = Init
@@ -20,6 +22,8 @@ data Init = Init
   , me :: UserId
   , payments :: [Payment]
   , incomes :: [Income]
+  , categories :: [Category]
+  , paymentCategories :: [PaymentCategory]
   } deriving (Show, Generic)
 
 instance ToJSON Init
diff --git a/src/server/Model/Json/PaymentCategory.hs b/src/server/Model/Json/PaymentCategory.hs
new file mode 100644
index 0000000..edd4388
--- /dev/null
+++ b/src/server/Model/Json/PaymentCategory.hs
@@ -0,0 +1,19 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Model.Json.PaymentCategory
+  ( PaymentCategory(..)
+  ) where
+
+import GHC.Generics
+
+import Data.Aeson
+import Data.Text (Text)
+
+import Model.Database (CategoryId)
+
+data PaymentCategory = PaymentCategory
+  { name :: Text
+  , category :: CategoryId
+  } deriving (Show, Generic)
+
+instance ToJSON PaymentCategory
diff --git a/src/server/Model/Message/Key.hs b/src/server/Model/Message/Key.hs
index d00d8b8..36b3ba0 100644
--- a/src/server/Model/Message/Key.hs
+++ b/src/server/Model/Message/Key.hs
@@ -77,6 +77,8 @@ data Key =
 
   | PaymentName
   | PaymentCost
+  | PaymentDate
+  | PaymentCategory
   | PaymentPunctual
   | PaymentMonthly
 
@@ -85,6 +87,20 @@ data Key =
   | Delete
   | ConfirmPaymentDelete
 
+  -- Categories
+
+  | Categories
+  | NoCategories
+  | CategoryNotDeleted
+  | AddCategory
+  | CloneCategory
+  | EditCategory
+  | ConfirmCategoryDelete
+  | CategoryName
+  | CategoryColor
+  | Color
+  | UsedCategory
+
   -- Statistics
 
   | Statistics
@@ -94,6 +110,7 @@ data Key =
   -- Income
 
   | CumulativeIncomesSince
+  | NoIncome
   | Income
   | MonthlyNetIncomes
   | AddIncome
@@ -101,6 +118,7 @@ data Key =
   | EditIncome
   | IncomeNotDeleted
   | IncomeAmount
+  | IncomeDate
   | ConfirmIncomeDelete
   | Add
 
@@ -110,6 +128,7 @@ data Key =
   | InvalidString
   | InvalidDate
   | InvalidInt
+  | InvalidCategory
   | SmallerIntThan
   | GreaterIntThan
 
@@ -121,6 +140,9 @@ data Key =
   | CreateIncomeError
   | EditIncomeError
   | DeleteIncomeError
+  | CreateCategoryError
+  | EditCategoryError
+  | DeleteCategoryError
   | SignOutError
 
   -- Dialog
@@ -128,6 +150,10 @@ data Key =
   | Confirm
   | Undo
 
+  -- Page not found
+
+  | PageNotFound
+
   -- Weekly report
 
   | WeeklyReport
@@ -151,9 +177,10 @@ data Key =
 
   -- Http error
 
+  | BadUrl
   | Timeout
   | NetworkError
-  | UnexpectedPayload
+  | BadPayload
 
   deriving (Enum, Bounded, Show)
 
diff --git a/src/server/Model/Message/Translations.hs b/src/server/Model/Message/Translations.hs
index 23e3a6c..6565344 100644
--- a/src/server/Model/Message/Translations.hs
+++ b/src/server/Model/Message/Translations.hs
@@ -295,6 +295,63 @@ m l NoPayment =
     English -> "No payment found from your search criteria."
     French  -> "Aucun paiement ne correspond à vos critères de recherches."
 
+-- Categories
+
+m l Categories =
+  case l of
+    English -> "Categories"
+    French  -> "Catégories"
+
+m l NoCategories =
+  case l of
+    English -> "No category."
+    French  -> "Aucune catégorie."
+
+m l CategoryNotDeleted =
+  case l of
+    English -> "The category could not have been deleted."
+    French  -> "La catégorie n'a pas pu être supprimé."
+
+m l AddCategory =
+  case l of
+    English -> "Add an category"
+    French  -> "Ajouter une catégorie"
+
+m l CloneCategory =
+  case l of
+    English -> "Clone an category"
+    French  -> "Cloner une catégorie"
+
+m l EditCategory =
+  case l of
+    English -> "Edit an category"
+    French  -> "Modifier une catégorie"
+
+m l ConfirmCategoryDelete =
+  case l of
+    English -> "Are you sure to delete this category ?"
+    French  -> "Voulez-vous vraiment supprimer cette catégorie ?"
+
+m l CategoryName =
+  case l of
+    English -> "Name"
+    French  -> "Nom"
+
+m l CategoryColor =
+  case l of
+    English -> "Color"
+    French  -> "Couleur"
+
+m l Color =
+  case l of
+    English -> "Color"
+    French  -> "Couleur"
+
+m l UsedCategory =
+  case l of
+    English -> "This category is currently being used"
+    French  -> "Cette catégorie est utilisée actuellement"
+
 -- Statistics
 
 m l Statistics =
@@ -322,6 +379,16 @@ m l PaymentCost =
     English -> "Cost"
     French  -> "Coût"
 
+m l PaymentDate =
+  case l of
+    English -> "Date"
+    French  -> "Date"
+
+m l PaymentCategory =
+  case l of
+    English -> "Category"
+    French  -> "Catégorie"
+
 m l PaymentPunctual =
   case l of
     English -> "Punctual"
@@ -359,6 +426,11 @@ m l CumulativeIncomesSince =
     English -> "Cumulative incomes since {1}"
     French  -> "Revenus nets cumulés depuis le {1}"
 
+m l NoIncome =
+  case l of
+    English -> "No income."
+    French  -> "Aucun revenu."
+
 m l Income =
   case l of
     English -> "Income"
@@ -394,6 +466,11 @@ m l IncomeAmount =
     English -> "Amount"
     French  -> "Montant"
 
+m l IncomeDate =
+  case l of
+    English -> "Date"
+    French  -> "Date"
+
 m l ConfirmIncomeDelete =
   case l of
     English -> "Are you sure to delete this income ?"
@@ -426,6 +503,11 @@ m l InvalidInt =
     English -> "Integer required"
     French  -> "Entier requis"
 
+m l InvalidCategory =
+  case l of
+    English -> "Invalid category"
+    French  -> "Catégorie invalide"
+
 m l SmallerIntThan =
   case l of
     English -> "Integer bigger than {1} or equal required"
@@ -468,6 +550,21 @@ m l DeleteIncomeError =
     English -> "Error at income deletion"
     French  -> "Erreur lors de la suppression du revenu"
 
+m l CreateCategoryError =
+  case l of
+    English -> "Error at category creation"
+    French  -> "Erreur lors de la création de la catégorie"
+
+m l EditCategoryError =
+  case l of
+    English -> "Error at category edition"
+    French  -> "Erreur lors de la modification de la catégorie"
+
+m l DeleteCategoryError =
+  case l of
+    English -> "Error at category deletion"
+    French  -> "Erreur lors de la suppression de la catégorie"
+
 m l SignOutError =
   case l of
     English -> "Error at sign out"
@@ -485,6 +582,13 @@ m l Undo =
     English -> "Undo"
     French  -> "Annuler"
 
+-- Page not found
+
+m l PageNotFound =
+  case l of
+    English -> "Page not found"
+    French  -> "Page introuvable"
+
 -- Weekly report
 
 m l WeeklyReport =
@@ -579,6 +683,11 @@ m l IsNotPayedFrom =
 
 -- Http error
 
+m l BadUrl =
+  case l of
+    English -> "URL not valid"
+    French  -> "l'URL n'est pas valide"
+
 m l Timeout =
   case l of
     English -> "Timeout server error"
@@ -589,7 +698,7 @@ m l NetworkError =
     English -> "Network can not be reached"
     French  -> "Le serveur n'est pas accessible"
 
-m l UnexpectedPayload =
+m l BadPayload =
   case l of
-    English -> "Unexpected payload server error"
-    French  -> "Contenu inattendu du en provenance du serveur"
+    English -> "Bad payload server error"
+    French  -> "Contenu inattendu en provenance du serveur"
diff --git a/src/server/Model/Payment.hs b/src/server/Model/Payment.hs
index ac6cf0a..d8caaa8 100644
--- a/src/server/Model/Payment.hs
+++ b/src/server/Model/Payment.hs
@@ -1,7 +1,8 @@
 {-# LANGUAGE OverloadedStrings #-}
 
 module Model.Payment
-  ( list
+  ( find
+  , list
   , listMonthly
   , create
   , editOwn
@@ -22,11 +23,11 @@ import Model.Database
 import Model.Frequency
 import qualified Model.Json.Payment as P
 
+find :: PaymentId -> Persist (Maybe (Entity Payment))
+find paymentId = selectFirst [ PaymentId ==. paymentId ] []
+
 list :: Persist [P.Payment]
-list =
-  map getJsonPayment <$> selectList
-    [ PaymentDeletedAt ==. Nothing ]
-    []
+list = map getJsonPayment <$> selectList [ PaymentDeletedAt ==. Nothing ] []
 
 listMonthly :: Persist [Entity Payment]
 listMonthly =
diff --git a/src/server/Model/PaymentCategory.hs b/src/server/Model/PaymentCategory.hs
new file mode 100644
index 0000000..6df77e2
--- /dev/null
+++ b/src/server/Model/PaymentCategory.hs
@@ -0,0 +1,55 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+module Model.PaymentCategory
+  ( list
+  , listByCategory
+  , set
+  , edit
+  , delete
+  ) where
+
+import Data.Maybe (isJust)
+import Data.Text (Text)
+import Data.Time.Clock (getCurrentTime)
+import qualified Data.Text as T
+
+import Control.Monad.IO.Class (liftIO)
+
+import Database.Persist
+
+import Model.Database
+import qualified Model.Json.PaymentCategory as Json
+import qualified Utils.Text as T
+
+list :: Persist [Json.PaymentCategory]
+list = map getJsonPaymentCategory <$> selectList [] []
+
+listByCategory :: CategoryId -> Persist [Entity PaymentCategory]
+listByCategory category = selectList [ PaymentCategoryCategory ==. category ] []
+
+getJsonPaymentCategory :: Entity PaymentCategory -> Json.PaymentCategory
+getJsonPaymentCategory entity =
+  Json.PaymentCategory (paymentCategoryName pc) (paymentCategoryCategory pc)
+  where pc = entityVal entity
+
+set :: Text -> CategoryId -> Persist ()
+set name category = edit name name category
+
+edit :: Text -> Text -> CategoryId -> Persist ()
+edit oldName newName category = do
+  now <- liftIO getCurrentTime
+  mbPaymentCategory <- selectFirst [PaymentCategoryName ==. (formatPaymentName oldName)] []
+  if isJust mbPaymentCategory
+    then
+      updateWhere
+        [ PaymentCategoryName ==. (formatPaymentName oldName) ]
+        [ PaymentCategoryName =. (formatPaymentName newName)
+        , PaymentCategoryCategory =. category
+        , PaymentCategoryEditedAt =. Just now
+        ]
+    else do
+      _ <- insert $ PaymentCategory (formatPaymentName newName) category now Nothing
+      return ()
+
+formatPaymentName :: Text -> Text
+formatPaymentName = T.unaccent . T.toLower
diff --git a/src/server/Model/User.hs b/src/server/Model/User.hs
index 696ef4f..ab39822 100644
--- a/src/server/Model/User.hs
+++ b/src/server/Model/User.hs
@@ -1,8 +1,8 @@
 module Model.User
-  ( getUsers
+  ( list
   , getUser
+  , getJson
   , findUser
-  , getJsonUser
   , createUser
   , deleteUser
   ) where
@@ -18,8 +18,8 @@ import Database.Persist
 import Model.Database
 import qualified Model.Json.User as Json
 
-getUsers :: Persist [Entity User]
-getUsers = selectList [] [Desc UserCreation]
+list :: Persist [Entity User]
+list = selectList [] [Desc UserCreation]
 
 getUser :: Text -> Persist (Maybe (Entity User))
 getUser email = selectFirst [UserEmail ==. email] []
@@ -27,8 +27,8 @@ getUser email = selectFirst [UserEmail ==. email] []
 findUser :: UserId -> [Entity User] -> Maybe User
 findUser i = fmap entityVal . find ((==) i . entityKey)
 
-getJsonUser :: Entity User -> Json.User
-getJsonUser userEntity =
+getJson :: Entity User -> Json.User
+getJson userEntity =
   let user = entityVal userEntity
   in  Json.User (entityKey userEntity) (userName user) (userEmail user)
 
diff --git a/src/server/Utils/Text.hs b/src/server/Utils/Text.hs
new file mode 100644
index 0000000..5ed77e4
--- /dev/null
+++ b/src/server/Utils/Text.hs
@@ -0,0 +1,41 @@
+module Utils.Text
+  ( unaccent
+  ) where
+
+import Data.Text (Text)
+import qualified Data.Text as T
+
+unaccent :: Text -> Text
+unaccent = T.map unaccentChar
+
+unaccentChar :: Char -> Char
+unaccentChar c = case c of
+  'à' -> 'a'
+  'á' -> 'a'
+  'â' -> 'a'
+  'ã' -> 'a'
+  'ä' -> 'a'
+  'ç' -> 'c'
+  'è' -> 'e'
+  'é' -> 'e'
+  'ê' -> 'e'
+  'ë' -> 'e'
+  'ì' -> 'i'
+  'í' -> 'i'
+  'î' -> 'i'
+  'ï' -> 'i'
+  'ñ' -> 'n'
+  'ò' -> 'o'
+  'ó' -> 'o'
+  'ô' -> 'o'
+  'õ' -> 'o'
+  'ö' -> 'o'
+  'š' -> 's'
+  'ù' -> 'u'
+  'ú' -> 'u'
+  'û' -> 'u'
+  'ü' -> 'u'
+  'ý' -> 'y'
+  'ÿ' -> 'y'
+  'ž' -> 'z'
+  _ -> c
diff --git a/src/server/View/Mail/WeeklyReport.hs b/src/server/View/Mail/WeeklyReport.hs
index f76fb0e..e33459c 100644
--- a/src/server/View/Mail/WeeklyReport.hs
+++ b/src/server/View/Mail/WeeklyReport.hs
@@ -48,7 +48,7 @@ body conf users paymentsByStatus incomesByStatus =
     then
       getMessage K.WeeklyReportEmpty
     else
-      T.intercalate "\n\n" . catMaybes . concat $
+      T.intercalate "\n" . catMaybes . concat $
         [ map (\s -> paymentSection s conf users <$> M.lookup s paymentsByStatus) statuses
         , map (\s -> incomeSection s conf users <$> M.lookup s incomesByStatus) statuses
         ]
@@ -119,6 +119,6 @@ section :: Text -> [Text] -> Text
 section title items =
   T.concat
     [ title
-    , "\n"
+    , "\n\n"
     , T.unlines . map ("  - " <>) $ items
     ]