Touch, multitouch and gesture input

The touch event handling features of the Flash Platform include input from a single point of contact or multiple points of contact on touch-enabled devices. And, the Flash runtimes handle events that combine multiple touch points with movement to create a gesture. In other words, Flash runtimes interpret two types of input:

Touch
input with a single point device such as a finger, stylus, or other tool on a touch-enabled device. Some devices support multiple simultaneous points of contact with a finger or stylus.

Multitouch
input with more than one simultaneous point of contact.

Gesture
Input interpreted by a device or operating system in response to one or more touch events. For example, a user rotates two fingers simultaneously, and the device or operating system interprets that touch input as a rotation gesture. Some gestures are performed with one finger or touch point, and some gestures require multiple touch points. The device or operating system establishes the type of gesture to assign to the input.

Both touch and gesture input can be multitouch input depending on the user's device. ActionScript provides API for handling touch events, gesture events, and individually tracked touch events for multitouch input.

Note: Listening for touch and gesture events can consume a significant amount of processing resources (equivalent to rendering several frames per second), depending on the computing device and operating system. It is often better to use mouse events when you do not actually need the extra functionality provided by touch or gestures. When you do use touch or gesture events, consider reducing the amount of graphical changes that can occur, especially when such events can be dispatched rapidly, as during a pan, rotate, or zoom operation. For example, you could stop animation within a component while the user resizes it using a zoom gesture.