cancelPreviousPerformRequestWithTarget is not canceling my previously delayed thread started with performSelector

Answer 1

-cancelPreviousPerformRequestsWithTarget:selector:object: is a class method on NSRunLoop, not NSObject. You might start by fixing that. I haven't found that method to be entirely reliable in the past, though, so if you continue having problems then you might need to look for another solution.

Answer 2

I found my issue, it didn't have anything to do with my calls to performSelector. I found that you have to set your MKMapView and CLlocationManager's delgate to nil before releasing them. Otherwise they will continue working even though you've released the instances and they have the potential to crash your app.

Thanks for your help Noah!.