Which methods are called when user presses home button and double presses it again to return

Question

I want to know which methods (events) are called when user presses home button and double presses it again to return to my app.

Answer 1

applicationDidEnterBackground
applicationWillEnterForeground

These all called in the app delegate

All details can be found here: http://developer.apple.com/library/ios/#documentation/uikit/reference/UIApplicationDelegate_Protocol/Reference/Reference.html