Today my app approved, but I got emails from users says it crash. I figured out that
[[UIApplication sharedApplication] setStatusBarHidden:YES withAnimation:
I'd recommend you to use the following snipplet of code instead of checking against the version of the os, rather check if a selector is currently available.
if([[UIApplication sharedApplication] respondsToSelector:@selector(setStatusBarHidden: withAnimation:)])
[[UIApplication sharedApplication] setStatusBarHidden:NO withAnimation:UIStatusBarAnimationFade];
else
[[UIApplication sharedApplication] setStatusBarHidden:NO animated:YES];