My iOS app freezes but no error appears

Question

Does any body know what I need to check if app freezes after some time? I mean, I can see the app in the iPhone screen but no view responds.

I did some google and i fou

Answer 1

Generally, it is highly recommended to perform on the main thread all animations method and interface manipulation, and to put in background tasks like download data from your server, etc...

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
    //here everything you want to perform in background

    dispatch_async(dispatch_get_main_queue(), ^{ 
        //call back to main queue to update user interface
    });
});

Source : http://www.raywenderlich.com/31166/25-ios-app-performance-tips-tricks