Question

I have a timer that have to count up to 8 hours (28800 second)
after that it should be released

im wondering how to keep the timer running at the background and/or when application is closed?

this is the NSTimer :

stopWatchTimer = [NSTimer scheduledTimerWithTimeInterval:1.0
                                                      target:self
                                                    selector:@selector(updateTimer)
                                                    userInfo:nil
                                                     repeats:YES];

and this is my condition :

 counter++;

if (counter >= 28800) {
    [stopWatchTimer invalidate];
    counter =0;

    timeLabel.text = @"Time Out";
}

Answer 1

You can’t – once your app is closed then it’s not running anymore so the timer won’t be running either.

Take a look at local notifications?