For my case handling UIDeviceOrientationDidChangeNotification was not good solution as it is called more frequent and UIDeviceOrientation is not always equal to UIInterfaceOrientation because of (FaceDown, FaceUp).
I handle it using UIApplicationDidChangeStatusBarOrientationNotification:
//To add the notification
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(didChangeOrientation:)
//to remove the
[[NSNotificationCenter defaultCenter]removeObserver:self name:UIDeviceOrientationDidChangeNotification object:nil];
...
- (void)didChangeOrientation:(NSNotification *)notification
{
UIInterfaceOrientation orientation = [UIApplication sharedApplication].statusBarOrientation;
if (UIInterfaceOrientationIsLandscape(orientation)) {
NSLog(@"Landscape");
}
else {
NSLog(@"Portrait");
}
}