Recently I am viewing Games category in IPhone [device] app store. For a particular game there is a "Tell a Friend" button on the nav bar.Tapping it opens a new mail creation screen with "Cancel" and "Send" buttons on nav bar. I want to know: -The new mail creation screen is from seperate application [Mail.app] or an inbuilt screen in app store. It seems to me that the app store application is paused while mail app is in process, is it right? Does there exists any role of UIAppDelegate's applicationDidBecomeActive? How can we pause an app?