How to stop running the app when you double tap the home button or go to the home page?

Question

How can I stop my game when I am on home or in the double click place, because my game continue and when I open it again I already lose.

Answer 1

You need to add code to applicationWillResignActive: in your app delegate.

This question also has some discussion on this topic.

Answer 2

It's actually much better policy to sign up for UIApplicationWillResignActiveNotification.

NSNotificationCenter.defaultCenter().addObserverForName(UIApplicationWillResignActiveNotification, object: nil, queue: nil) { (notification:NSNotification) in
        self.pause()
    }

Otherwise you will need to get references to your UIApplicationMain, which is basically the wrong way to do things. This is what NSNotificationCenter was made for.