I'm making a universal iPad/iPhone app which can use the iPad's VGA out connector to mirror the content of the app on an external screen. However, the iPhone does not have this functionality. given the following code,

[[NSNotificationCenter defaultCenter] addObserver:self
         selector:@selector(screenInfoNotificationReceieved:) 
          name:UIScreenDidConnectNotification
           object:nil];

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(screenInfoNotificationReceieved:) name:UIScreenDidDisconnectNotification object:nil];

I get this error on the phone at launch (works fine in ipad) "dyld: Symbol not found: _UIScreenDidConnectNotification"

presumably because UIScreenDidConnectNotification doesnt' exist yet in 3.13. How do I check for this at runtime?