I've seen that I can detect changes in screen brightness by registering as an observer for
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(brightnessDidChange:) name:UIScreenBrightnessDidChangeNotification object:nil];
NSLog(@"Brightness did change");
I think it is not possible, we can only get
notification when Brightness change by the system or manually. we can't differentiate both.