diff --git a/browser/metro/base/content/input.js b/browser/metro/base/content/input.js
index e0bedf39d11c..7693d84a7692 100644
--- a/browser/metro/base/content/input.js
+++ b/browser/metro/base/content/input.js
@@ -1037,14 +1037,10 @@ var GestureModule = {
  */
 var InputSourceHelper = {
   isPrecise: false,
-  touchIsActive: false,
 
   init: function ish_init() {
-    window.addEventListener("mousemove", this, true);
-    window.addEventListener("mousedown", this, true);
-    window.addEventListener("touchstart", this, true);
-    window.addEventListener("touchend", this, true);
-    window.addEventListener("touchcancel", this, true);
+    Services.obs.addObserver(this, "metro_precise_input", false);
+    Services.obs.addObserver(this, "metro_imprecise_input", false);
   },
 
   _precise: function () {
@@ -1061,37 +1057,17 @@ var InputSourceHelper = {
     }
   },
 
-  handleEvent: function ish_handleEvent(aEvent) {
-    switch(aEvent.type) {
-      case "touchstart":
+  observe: function BrowserUI_observe(aSubject, aTopic, aData) {
+    switch (aTopic) {
+      case "metro_precise_input":
+        this._precise();
+        break;
+      case "metro_imprecise_input":
         this._imprecise();
-        this.touchIsActive = true;
-        break;
-      case "touchend":
-      case "touchcancel":
-        this.touchIsActive = false;
-        break;
-      default:
-        // Ignore mouse movement when touch is active. Prevents both mouse scrollbars
-        // and touch scrollbars from displaying at the same time. Also works around
-        // odd win8 bug involving an erant mousemove event after a touch sequence
-        // starts (bug 896017).
-        if (this.touchIsActive) {
-          return;
-        }
-
-        switch (aEvent.mozInputSource) {
-          case Ci.nsIDOMMouseEvent.MOZ_SOURCE_MOUSE:
-          case Ci.nsIDOMMouseEvent.MOZ_SOURCE_PEN:
-          case Ci.nsIDOMMouseEvent.MOZ_SOURCE_ERASER:
-          case Ci.nsIDOMMouseEvent.MOZ_SOURCE_CURSOR:
-            this._precise();
-            break;
-        }
         break;
     }
   },
-  
+
   fireUpdate: function fireUpdate() {
     if (this.isPrecise) {
       this._fire("MozPrecisePointer");
diff --git a/widget/windows/winrt/MetroInput.cpp b/widget/windows/winrt/MetroInput.cpp
index 2318b2ff5277..5d96780f4c97 100644
--- a/widget/windows/winrt/MetroInput.cpp
+++ b/widget/windows/winrt/MetroInput.cpp
@@ -206,6 +206,7 @@ MetroInput::MetroInput(MetroWidget* aWidget,
                        UI::Core::ICoreWindow* aWindow)
               : mWidget(aWidget),
                 mChromeHitTestCacheForTouch(false),
+                mCurrentInputLevel(LEVEL_IMPRECISE),
                 mWindow(aWindow)
 {
   LogFunction();
@@ -240,6 +241,51 @@ MetroInput::~MetroInput()
   UnregisterInputEvents();
 }
 
+
+/**
+ * Tracks the current input level (precise/imprecise) and fires an observer
+ * when the mode changes.
+ */
+void
+MetroInput::UpdateInputLevel(InputPrecisionLevel aInputLevel)
+{
+  // ignore mouse input if we have active touch input.
+  if (aInputLevel == LEVEL_PRECISE && mTouches.Count() > 0) {
+    return;
+  }
+  if (mCurrentInputLevel != aInputLevel) {
+    mCurrentInputLevel = aInputLevel;
+    MetroUtils::FireObserver(mCurrentInputLevel == LEVEL_PRECISE ?
+                               "metro_precise_input" : "metro_imprecise_input");
+  }
+}
+
+/**
+ * Processes an IEdgeGestureEventArgs and returns the input source type
+ * for the event. Also updates input level via UpdateInputLevel.
+ */
+uint16_t
+MetroInput::ProcessInputTypeForGesture(UI::Input::IEdgeGestureEventArgs* aArgs)
+{
+  MOZ_ASSERT(aArgs);
+  UI::Input::EdgeGestureKind kind;
+  aArgs->get_Kind(&kind);
+  switch(kind) {
+    case UI::Input::EdgeGestureKind::EdgeGestureKind_Touch:
+      UpdateInputLevel(LEVEL_PRECISE);
+      return nsIDOMMouseEvent::MOZ_SOURCE_TOUCH;
+    break;
+    case UI::Input::EdgeGestureKind::EdgeGestureKind_Keyboard:
+      return nsIDOMMouseEvent::MOZ_SOURCE_KEYBOARD;
+    break;
+    case UI::Input::EdgeGestureKind::EdgeGestureKind_Mouse:
+      UpdateInputLevel(LEVEL_IMPRECISE);
+      return nsIDOMMouseEvent::MOZ_SOURCE_MOUSE;
+    break;
+  }
+  return nsIDOMMouseEvent::MOZ_SOURCE_UNKNOWN;
+}
+
 /**
  * When the user swipes her/his finger in from the top of the screen,
  * we receive this event.
@@ -263,8 +309,7 @@ MetroInput::OnEdgeGestureStarted(UI::Input::IEdgeGesture* sender,
   mModifierKeyState.Update();
   mModifierKeyState.InitInputEvent(geckoEvent);
   geckoEvent.time = ::GetMessageTime();
-
-  geckoEvent.inputSource = nsIDOMMouseEvent::MOZ_SOURCE_TOUCH;
+  geckoEvent.inputSource = ProcessInputTypeForGesture(aArgs);
 
   // Safe
   DispatchEventIgnoreStatus(&geckoEvent);
@@ -295,8 +340,7 @@ MetroInput::OnEdgeGestureCanceled(UI::Input::IEdgeGesture* sender,
   mModifierKeyState.Update();
   mModifierKeyState.InitInputEvent(geckoEvent);
   geckoEvent.time = ::GetMessageTime();
-
-  geckoEvent.inputSource = nsIDOMMouseEvent::MOZ_SOURCE_TOUCH;
+  geckoEvent.inputSource = ProcessInputTypeForGesture(aArgs);
 
   // Safe
   DispatchEventIgnoreStatus(&geckoEvent);
@@ -326,15 +370,7 @@ MetroInput::OnEdgeGestureCompleted(UI::Input::IEdgeGesture* sender,
   mModifierKeyState.Update();
   mModifierKeyState.InitInputEvent(geckoEvent);
   geckoEvent.time = ::GetMessageTime();
-
-  UI::Input::EdgeGestureKind value;
-  aArgs->get_Kind(&value);
-
-  if (value == UI::Input::EdgeGestureKind::EdgeGestureKind_Keyboard) {
-    geckoEvent.inputSource = nsIDOMMouseEvent::MOZ_SOURCE_KEYBOARD;
-  } else {
-    geckoEvent.inputSource = nsIDOMMouseEvent::MOZ_SOURCE_TOUCH;
-  }
+  geckoEvent.inputSource = ProcessInputTypeForGesture(aArgs);
 
   // Safe
   DispatchEventIgnoreStatus(&geckoEvent);
@@ -391,6 +427,7 @@ MetroInput::OnPointerNonTouch(UI::Input::IPointerPoint* aPoint) {
       event->message = NS_MOUSE_BUTTON_UP;
       break;
   }
+  UpdateInputLevel(LEVEL_PRECISE);
   InitGeckoMouseEventFromPointerPoint(event, aPoint);
   DispatchAsyncEventIgnoreStatus(event);
 }
@@ -430,6 +467,8 @@ MetroInput::OnPointerPressed(UI::Core::ICoreWindow* aSender,
   }
 
   // This is touch input.
+  UpdateInputLevel(LEVEL_IMPRECISE);
+
   // Create the new touch point and add it to our event.
   uint32_t pointerId;
   currentPoint->get_PointerId(&pointerId);
@@ -517,6 +556,8 @@ MetroInput::OnPointerMoved(UI::Core::ICoreWindow* aSender,
   }
 
   // This is touch input.
+  UpdateInputLevel(LEVEL_IMPRECISE);
+
   // Get the touch associated with this touch point.
   uint32_t pointerId;
   currentPoint->get_PointerId(&pointerId);
@@ -614,6 +655,8 @@ MetroInput::OnPointerReleased(UI::Core::ICoreWindow* aSender,
   }
 
   // This is touch input.
+  UpdateInputLevel(LEVEL_IMPRECISE);
+
   // Get the touch associated with this touch point.
   uint32_t pointerId;
   currentPoint->get_PointerId(&pointerId);
@@ -748,9 +791,11 @@ MetroInput::OnPointerEntered(UI::Core::ICoreWindow* aSender,
     WidgetMouseEvent* event =
       new WidgetMouseEvent(true, NS_MOUSE_ENTER, mWidget.Get(),
                            WidgetMouseEvent::eReal, WidgetMouseEvent::eNormal);
+    UpdateInputLevel(LEVEL_PRECISE);
     InitGeckoMouseEventFromPointerPoint(event, currentPoint.Get());
     DispatchAsyncEventIgnoreStatus(event);
   }
+  UpdateInputLevel(LEVEL_IMPRECISE);
   return S_OK;
 }
 
@@ -779,9 +824,11 @@ MetroInput::OnPointerExited(UI::Core::ICoreWindow* aSender,
     WidgetMouseEvent* event =
       new WidgetMouseEvent(true, NS_MOUSE_EXIT, mWidget.Get(),
                            WidgetMouseEvent::eReal, WidgetMouseEvent::eNormal);
+    UpdateInputLevel(LEVEL_PRECISE);
     InitGeckoMouseEventFromPointerPoint(event, currentPoint.Get());
     DispatchAsyncEventIgnoreStatus(event);
   }
+  UpdateInputLevel(LEVEL_IMPRECISE);
   return S_OK;
 }
 
diff --git a/widget/windows/winrt/MetroInput.h b/widget/windows/winrt/MetroInput.h
index 6b38c00f01f8..f676b384263a 100644
--- a/widget/windows/winrt/MetroInput.h
+++ b/widget/windows/winrt/MetroInput.h
@@ -155,6 +155,14 @@ private:
 
   ModifierKeyState mModifierKeyState;
 
+  // Tracking input level
+  enum InputPrecisionLevel {
+    LEVEL_PRECISE,
+    LEVEL_IMPRECISE
+  };
+  InputPrecisionLevel mCurrentInputLevel;
+  void UpdateInputLevel(InputPrecisionLevel aInputLevel);
+
   // Initialization/Uninitialization helpers
   void RegisterInputEvents();
   void UnregisterInputEvents();
@@ -174,6 +182,7 @@ private:
                                 Point const& aPosition,
                                 uint32_t aMagEventType,
                                 uint32_t aRotEventType);
+  uint16_t ProcessInputTypeForGesture(IEdgeGestureEventArgs* aArgs);
 
   // The W3C spec states that "whether preventDefault has been called" should
   // be tracked on a per-touchpoint basis, but it also states that touchstart