GameTimer is a light-weight timer that you can use for iOS games. It can be enhanced easily for more complex projects. One use is to update a progressbar whilst the main timer is running.
GameTimer incorporates 2 timers that work in unison - referred to as longTimer and shortTimer. The shortTimer acts as a 'finer' resolution timer that can be used to update a progressbar or continually poll a network connection (for example). It's interval is usually set to a fraction of the longTimer.
GameTimer automatically pauses when the app enters the BACKGROUND and 'unpauses' when the app is ACTIVE again.