diff --git a/quickstep/res/values/strings.xml b/quickstep/res/values/strings.xml
index 6af0d60..88c98c0 100644
--- a/quickstep/res/values/strings.xml
+++ b/quickstep/res/values/strings.xml
@@ -193,6 +193,8 @@
     <string name="action_split">Split</string>
     <!-- Label for toast with instructions for split screen selection mode. [CHAR_LIMIT=50] -->
     <string name="toast_split_select_app">Tap another app to use splitscreen</string>
+    <!-- Label for toast when app selected for split isn't supported. [CHAR_LIMIT=50] -->
+    <string name="toast_split_app_unsupported">App does not support split-screen.</string>
     <!-- Message shown when an action is blocked by a policy enforced by the app or the organization managing the device. [CHAR_LIMIT=NONE] -->
     <string name="blocked_by_policy">This action isn\'t allowed by the app or your organization</string>
 
diff --git a/quickstep/src/com/android/quickstep/views/RecentsView.java b/quickstep/src/com/android/quickstep/views/RecentsView.java
index f7a9562..5cad31d 100644
--- a/quickstep/src/com/android/quickstep/views/RecentsView.java
+++ b/quickstep/src/com/android/quickstep/views/RecentsView.java
@@ -597,6 +597,8 @@
     private SplitConfigurationOptions.StagedSplitBounds mSplitBoundsConfig;
     private final Toast mSplitToast = Toast.makeText(getContext(),
             R.string.toast_split_select_app, Toast.LENGTH_SHORT);
+    private final Toast mSplitUnsupportedToast = Toast.makeText(getContext(),
+            R.string.toast_split_app_unsupported, Toast.LENGTH_SHORT);
 
     /**
      * Keeps track of the index of the TaskView that split screen was initialized with so we know
@@ -3847,6 +3849,11 @@
 
     public void confirmSplitSelect(TaskView taskView) {
         mSplitToast.cancel();
+        if (!taskView.getTask().isDockable) {
+            // Task not split screen supported
+            mSplitUnsupportedToast.show();
+            return;
+        }
         RectF secondTaskStartingBounds = new RectF();
         Rect secondTaskEndingBounds = new Rect();
         // TODO(194414938) starting bounds seem slightly off, investigate
@@ -3889,6 +3896,7 @@
         int duration = mActivity.getStateManager().getState().getTransitionDuration(getContext());
         PendingAnimation pendingAnim = new PendingAnimation(duration);
         mSplitToast.cancel();
+        mSplitUnsupportedToast.cancel();
         if (!animate) {
             resetFromSplitSelectionState();
             return pendingAnim;