Index: Thumb.cpp
===================================================================
--- Thumb.cpp	(revision 11481)
+++ Thumb.cpp	(revision 11482)
@@ -42,10 +42,12 @@
         {
             ReleaseMouseCapture();
         }
+        ReleaseAllTouchCaptures();
+
         SetReadOnlyProperty<bool>(IsDraggingProperty, false);
-        
-        DragCompletedEventArgs args(this, true, mCurrentScreenPosition.x - mStartScreenPosition.x, 
-            mCurrentScreenPosition.y - mStartScreenPosition.y);
+
+        Point offset = mCurrentScreenPosition - mStartScreenPosition;
+        DragCompletedEventArgs args(this, true, offset.x, offset.y);
         RaiseEvent(args);
     }
 }
@@ -278,6 +280,15 @@
     data->RegisterEvent(DragCompletedEvent, "DragCompleted", RoutingStrategy_Bubble);
     data->RegisterEvent(DragDeltaEvent, "DragDelta", RoutingStrategy_Bubble);
     data->RegisterEvent(DragStartedEvent, "DragStarted", RoutingStrategy_Bubble);
+
+    auto OnLostCapture = [](BaseComponent* sender, const EventArgs&)
+    {
+        Thumb* thumb = (Thumb*)sender;
+        thumb->CancelDrag();
+    };
+
+    data->RegisterEventHandler(LostMouseCaptureEvent, OnLostCapture);
+    data->RegisterEventHandler(LostTouchCaptureEvent, OnLostCapture);
 }
 
 NS_END_COLD_REGION