With the advent of Windows Phone, Silverlight transitioned from being a browser and desktop-only technology with a primarily mouse-driven UI, to a mobile device technology with a touch-driven UI.
To allow controls that were originally designed to work with mouse events to continue to function, the touch system was engineered so that touch events are automatically turned into (promoted to) mouse events. If a touch event is not suspended using the
SuspendMousePromotionUntilTouchUp method, then mouse events are automatically raised.
Promotion of a
TouchPoint to a mouse event occurs only with the primary touch point.
To prevent a touch event from being promoted to a mouse event, call the