Crash in background thread dones't affect main thread

Please post the crash log maybe even some code? Help us help you.

 

It may be that runtime exceptions are caught in background threads. The @catch could be in your code or a third-party library you're using or in framework code.

On MacOS X exceptions are caught by the event loop so they don't kill your app. As we all know on iOS in the main thread there is no default @catch block for runtime exceptions. I'm not sure if there is an @catch block in a thread however. I have seen comments like yours though.