So far we have only explored actions involving a single touch point. Our next goal is to learn how to apply more advanced action events with
multi-touch. One of the common actions is the pinch-in/out for zooming out/in respectively. The Safari browser for iOS supports this motion with
gestureend events. Whenever there are two or more fingers touching the screen, the
gesturestart event is fired. Then the
gesturechange event is triggered when the fingers are moved on the screen. When the fingers leave the screen, the
gestureend event is generated. In returning control to the event handler, if the action is recognized, a certain property in the event object ...