what delegate method that will called when an app close in IOS?

just like my question, I just want to know what 开发者_如何学Pythondelegate method that will called when an app close? I was thought that it was ApplicationWillTerminate, but no, that delegate method just called if the app spend to much memory and no memory left, so the system called that method.

So, what delegate method that will called when an app close?

- (void)applicationDidEnterBackground:(UIApplication *)application