A multi-touch gesture can be used for many functions, and can incorporate both selecting and dragging in the same motion and is often achieved by using the thumb and index finger and moving them apart from ne another. The resulting action can differ depending on the application: the gesture could be used for selecting multiple on-screen objects in a file or for zooming on a map. But for each scenario, the developer will want to use different effects. Selecting multiple items may trigger a playback of simple single-click effects as each object is selected. For zooming, a haptic response that swells and fades in magnitude is more appropriate.
Image Credit: Chad Person (GestureWorks) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons