When touches Cancelled method get invoked in iPhone?

Question

I am able to understand that when user just touches the view, touches Began and Ended called. When user swipes their hand on a view, touches Moved method gets called. But when d

Answer 1

From the Apple Reference documents

Sent to the receiver when a system event (such as a low-memory warning) cancels a touch event.

Discussion

This method is invoked when the Cocoa Touch framework receives a system interruption requiring cancellation of the touch event; for this, it generates a UITouch object with a phase of UITouchPhaseCancel. The interruption is something that might cause the application to be no longer active or the view to be removed from the window

When an object receives a touchesCancelled:withEvent: message it should clean up any state information that was established in its touchesBegan:withEvent: implementation.

The default implementation of this method does nothing. However immediate UIKit subclasses of UIResponder, particularly UIView, forward the message up the responder chain.