diff --git a/src/com/android/launcher3/Launcher.java b/src/com/android/launcher3/Launcher.java
index f2610d6..58c4cf7 100644
--- a/src/com/android/launcher3/Launcher.java
+++ b/src/com/android/launcher3/Launcher.java
@@ -2409,13 +2409,6 @@
         sFolders.remove(folder.id);
     }
 
-    protected ComponentName getWallpaperPickerComponent() {
-        if (mLauncherCallbacks != null) {
-            return mLauncherCallbacks.getWallpaperPickerComponent();
-        }
-        return new ComponentName(getPackageName(), LauncherWallpaperPickerActivity.class.getName());
-    }
-
     /**
      * Registers various content observers. The current implementation registers
      * only a favorites observer to keep track of the favorites applications.
@@ -2780,9 +2773,8 @@
      */
     protected void onClickWallpaperPicker(View v) {
         if (LOGD) Log.d(TAG, "onClickWallpaperPicker");
-        final Intent pickWallpaper = new Intent(Intent.ACTION_SET_WALLPAPER);
-        pickWallpaper.setComponent(getWallpaperPickerComponent());
-        startActivityForResult(pickWallpaper, REQUEST_PICK_WALLPAPER);
+        startActivityForResult(new Intent(Intent.ACTION_SET_WALLPAPER).setPackage(getPackageName()),
+                REQUEST_PICK_WALLPAPER);
 
         if (mLauncherCallbacks != null) {
             mLauncherCallbacks.onClickWallpaperPicker(v);
diff --git a/src/com/android/launcher3/LauncherFiles.java b/src/com/android/launcher3/LauncherFiles.java
index ce277c1..699cb37 100644
--- a/src/com/android/launcher3/LauncherFiles.java
+++ b/src/com/android/launcher3/LauncherFiles.java
@@ -20,7 +20,8 @@
     public static final String LAUNCHER_PREFERENCES = "launcher.preferences";
     public static final String SHARED_PREFERENCES_KEY = "com.android.launcher3.prefs";
     public static final String WALLPAPER_CROP_PREFERENCES_KEY =
-            WallpaperCropActivity.class.getName();
+            "com.android.launcher3.WallpaperCropActivity";
+
     public static final String WALLPAPER_IMAGES_DB = "saved_wallpaper_images.db";
     public static final String WIDGET_PREVIEWS_DB = "widgetpreviews.db";
     public static final String APP_ICONS_DB = "app_icons.db";
diff --git a/src/com/android/launcher3/LauncherWallpaperPickerActivity.java b/src/com/android/launcher3/LauncherWallpaperPickerActivity.java
deleted file mode 100644
index 10fe013..0000000
--- a/src/com/android/launcher3/LauncherWallpaperPickerActivity.java
+++ /dev/null
@@ -1,30 +0,0 @@
-/*
- * Copyright (C) 2013 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.android.launcher3;
-
-import android.content.Intent;
-
-public class LauncherWallpaperPickerActivity extends WallpaperPickerActivity {
-    @Override
-    public void startActivityForResultSafely(Intent intent, int requestCode) {
-        Utilities.startActivityForResultSafely(this, intent, requestCode);
-    }
-    @Override
-    public boolean enableRotation() {
-        return Utilities.isRotationEnabled(this);
-    }
-}
diff --git a/src/com/android/launcher3/Workspace.java b/src/com/android/launcher3/Workspace.java
index 37265fe..7c12d4c 100644
--- a/src/com/android/launcher3/Workspace.java
+++ b/src/com/android/launcher3/Workspace.java
@@ -70,6 +70,7 @@
 import com.android.launcher3.compat.PackageInstallerCompat.PackageInstallInfo;
 import com.android.launcher3.compat.UserHandleCompat;
 import com.android.launcher3.util.Thunk;
+import com.android.launcher3.util.WallpaperUtils;
 
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -1315,10 +1316,10 @@
     protected void setWallpaperDimension() {
         new AsyncTask<Void, Void, Void>() {
             public Void doInBackground(Void ... args) {
-                String spKey = WallpaperCropActivity.getSharedPreferencesKey();
+                String spKey = LauncherFiles.WALLPAPER_CROP_PREFERENCES_KEY;
                 SharedPreferences sp =
                         mLauncher.getSharedPreferences(spKey, Context.MODE_MULTI_PROCESS);
-                LauncherWallpaperPickerActivity.suggestWallpaperDimension(mLauncher.getResources(),
+                WallpaperUtils.suggestWallpaperDimension(mLauncher.getResources(),
                         sp, mLauncher.getWindowManager(), mWallpaperManager,
                         mLauncher.overrideWallpaperDimensions());
                 return null;
diff --git a/src/com/android/launcher3/util/WallpaperUtils.java b/src/com/android/launcher3/util/WallpaperUtils.java
new file mode 100644
index 0000000..53b2acd
--- /dev/null
+++ b/src/com/android/launcher3/util/WallpaperUtils.java
@@ -0,0 +1,123 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.launcher3.util;
+
+import android.annotation.TargetApi;
+import android.app.WallpaperManager;
+import android.content.SharedPreferences;
+import android.content.res.Resources;
+import android.graphics.Point;
+import android.os.Build;
+import android.view.WindowManager;
+
+/**
+ * Utility methods for wallpaper management.
+ */
+public final class WallpaperUtils {
+
+    public static final String WALLPAPER_WIDTH_KEY = "wallpaper.width";
+    public static final String WALLPAPER_HEIGHT_KEY = "wallpaper.height";
+    public static final float WALLPAPER_SCREENS_SPAN = 2f;
+
+    public static void suggestWallpaperDimension(Resources res,
+            final SharedPreferences sharedPrefs,
+            WindowManager windowManager,
+            final WallpaperManager wallpaperManager, boolean fallBackToDefaults) {
+        final Point defaultWallpaperSize = WallpaperUtils.getDefaultWallpaperSize(res, windowManager);
+        // If we have saved a wallpaper width/height, use that instead
+
+        int savedWidth = sharedPrefs.getInt(WALLPAPER_WIDTH_KEY, -1);
+        int savedHeight = sharedPrefs.getInt(WALLPAPER_HEIGHT_KEY, -1);
+
+        if (savedWidth == -1 || savedHeight == -1) {
+            if (!fallBackToDefaults) {
+                return;
+            } else {
+                savedWidth = defaultWallpaperSize.x;
+                savedHeight = defaultWallpaperSize.y;
+            }
+        }
+
+        if (savedWidth != wallpaperManager.getDesiredMinimumWidth() ||
+                savedHeight != wallpaperManager.getDesiredMinimumHeight()) {
+            wallpaperManager.suggestDesiredDimensions(savedWidth, savedHeight);
+        }
+    }
+
+    /**
+     * As a ratio of screen height, the total distance we want the parallax effect to span
+     * horizontally
+     */
+    public static float wallpaperTravelToScreenWidthRatio(int width, int height) {
+        float aspectRatio = width / (float) height;
+
+        // At an aspect ratio of 16/10, the wallpaper parallax effect should span 1.5 * screen width
+        // At an aspect ratio of 10/16, the wallpaper parallax effect should span 1.2 * screen width
+        // We will use these two data points to extrapolate how much the wallpaper parallax effect
+        // to span (ie travel) at any aspect ratio:
+
+        final float ASPECT_RATIO_LANDSCAPE = 16/10f;
+        final float ASPECT_RATIO_PORTRAIT = 10/16f;
+        final float WALLPAPER_WIDTH_TO_SCREEN_RATIO_LANDSCAPE = 1.5f;
+        final float WALLPAPER_WIDTH_TO_SCREEN_RATIO_PORTRAIT = 1.2f;
+
+        // To find out the desired width at different aspect ratios, we use the following two
+        // formulas, where the coefficient on x is the aspect ratio (width/height):
+        //   (16/10)x + y = 1.5
+        //   (10/16)x + y = 1.2
+        // We solve for x and y and end up with a final formula:
+        final float x =
+            (WALLPAPER_WIDTH_TO_SCREEN_RATIO_LANDSCAPE - WALLPAPER_WIDTH_TO_SCREEN_RATIO_PORTRAIT) /
+            (ASPECT_RATIO_LANDSCAPE - ASPECT_RATIO_PORTRAIT);
+        final float y = WALLPAPER_WIDTH_TO_SCREEN_RATIO_PORTRAIT - x * ASPECT_RATIO_PORTRAIT;
+        return x * aspectRatio + y;
+    }
+
+    private static Point sDefaultWallpaperSize;
+
+    @TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR1)
+    public static Point getDefaultWallpaperSize(Resources res, WindowManager windowManager) {
+        if (sDefaultWallpaperSize == null) {
+            Point minDims = new Point();
+            Point maxDims = new Point();
+            windowManager.getDefaultDisplay().getCurrentSizeRange(minDims, maxDims);
+
+            int maxDim = Math.max(maxDims.x, maxDims.y);
+            int minDim = Math.max(minDims.x, minDims.y);
+
+            if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.JELLY_BEAN_MR1) {
+                Point realSize = new Point();
+                windowManager.getDefaultDisplay().getRealSize(realSize);
+                maxDim = Math.max(realSize.x, realSize.y);
+                minDim = Math.min(realSize.x, realSize.y);
+            }
+
+            // We need to ensure that there is enough extra space in the wallpaper
+            // for the intended parallax effects
+            final int defaultWidth, defaultHeight;
+            if (res.getConfiguration().smallestScreenWidthDp >= 720) {
+                defaultWidth = (int) (maxDim * wallpaperTravelToScreenWidthRatio(maxDim, minDim));
+                defaultHeight = maxDim;
+            } else {
+                defaultWidth = Math.max((int) (minDim * WALLPAPER_SCREENS_SPAN), maxDim);
+                defaultHeight = maxDim;
+            }
+            sDefaultWallpaperSize = new Point(defaultWidth, defaultHeight);
+        }
+        return sDefaultWallpaperSize;
+    }
+}