diff --git a/core/src/commonMain/kotlin/org/isoron/uhabits/backend/MainScreenDataSource.kt b/core/src/commonMain/kotlin/org/isoron/uhabits/backend/MainScreenDataSource.kt
index 043806bb7..3a2a470e9 100644
--- a/core/src/commonMain/kotlin/org/isoron/uhabits/backend/MainScreenDataSource.kt
+++ b/core/src/commonMain/kotlin/org/isoron/uhabits/backend/MainScreenDataSource.kt
@@ -20,7 +20,6 @@
 package org.isoron.uhabits.backend
 
 import org.isoron.platform.concurrency.*
-import org.isoron.platform.gui.*
 import org.isoron.platform.time.*
 import org.isoron.uhabits.models.*
 
@@ -28,13 +27,11 @@ class MainScreenDataSource(val habits: MutableMap<Int, Habit>,
                            val checkmarks: MutableMap<Habit, CheckmarkList>,
                            val taskRunner: TaskRunner) {
 
-    private val today = LocalDate(2019, 3, 30)
+    private val today = LocalDate(2019, 3, 30) /* TODO */
 
-    data class Data(val ids: List<Int>,
-                    val scores: List<Double>,
-                    val names: List<String>,
-                    val colors: List<PaletteColor>,
-                    val checkmarks: List<List<Int>>)
+    data class Data(val habits: List<Habit>,
+                    val currentScore: Map<Habit, Double>,
+                    val checkmarkValues: Map<Habit, List<Int>>)
 
     val observable = Observable<Listener>()
 
@@ -44,17 +41,14 @@ class MainScreenDataSource(val habits: MutableMap<Int, Habit>,
 
     fun requestData() {
         taskRunner.runInBackground {
-            val filteredHabits = habits.values.filter { h -> !h.isArchived }
-            val ids = filteredHabits.map { it.id }
-            val scores = filteredHabits.map { 0.0 }
-            val names = filteredHabits.map { it.name }
-            val colors = filteredHabits.map { it.color }
-            val ck = filteredHabits.map { habit ->
-                val allValues = checkmarks[habit]!!.getValuesUntil(today)
-                if (allValues.size <= 7) allValues
-                else allValues.subList(0, 7)
+            val filtered = habits.values.filter { h -> !h.isArchived }
+            val currentScores = filtered.associate { it to 0.0 /* TODO */}
+            val recentCheckmarks = filtered.associate {
+                val allValues = checkmarks[it]!!.getValuesUntil(today)
+                if (allValues.size <= 7) it to allValues
+                else it to allValues.subList(0, 7)
             }
-            val data = Data(ids, scores, names, colors, ck)
+            val data = Data(filtered, currentScores, recentCheckmarks)
             taskRunner.runInForeground {
                 observable.notifyListeners { listener ->
                     listener.onDataChanged(data)
diff --git a/ios/Application/Frontend/MainScreenController.swift b/ios/Application/Frontend/MainScreenController.swift
index 0689faf14..fd9d8645b 100644
--- a/ios/Application/Frontend/MainScreenController.swift
+++ b/ios/Application/Frontend/MainScreenController.swift
@@ -101,7 +101,7 @@ class MainScreenController: UITableViewController, MainScreenDataSourceListener
         self.dataSource = backend.mainScreenDataSource
         self.theme = backend.theme
         super.init(nibName: nil, bundle: nil)
-        self.dataSource.addListener(listener: self)
+        self.dataSource.observable.addListener(listener: self)
         self.dataSource.requestData()
     }
     
@@ -133,16 +133,16 @@ class MainScreenController: UITableViewController, MainScreenDataSourceListener
     }
     
     override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
-        return data?.names.count ?? 0
+        return data?.habits.count ?? 0
     }
     
     override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
         let row = indexPath.row
         let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! MainScreenCell
-        let color = theme.color(paletteIndex: data!.colors[row].index)
-        cell.update(name: data!.names[row],
-                    color: color,
-                    values: data!.checkmarks[row])
+        let habit = data!.habits[row]
+        cell.update(name: habit.name,
+                    color: theme.color(paletteIndex: habit.color.index),
+                    values: data!.checkmarkValues[habit]!)
         return cell
     }
     
@@ -164,7 +164,9 @@ class MainScreenController: UITableViewController, MainScreenDataSourceListener
     }
     
     override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
-        let color = theme.color(paletteIndex: data!.colors[indexPath.row].index)
-        self.navigationController?.pushViewController(ShowHabitController(theme: theme, color: color), animated: true)
+        let color = theme.color(paletteIndex: data!.habits[indexPath.row].color.index)
+        self.navigationController?.pushViewController(ShowHabitController(theme: theme,
+                                                                          color: color),
+                                                      animated: true)
     }
 }