You are not setting the delegate of the gestures:
UISwipeGestureRecognizer *swipeRight = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(didSwipeRight:)];
swipeRight.delegate = self;
swipeRight.numberOfTouchesRequired = 1;
[swipeRight setDirection:UISwipeGestureRecognizerDirectionRight];
UISwipeGestureRecognizer *swipeLeft = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(didSwipeLeft:)];
swipeLeft.delegate = self;
swipeLeft.numberOfTouchesRequired = 1;
[swipeLeft setDirection:UISwipeGestureRecognizerDirectionLeft];