It could be annoying that the camera pan-tilt position changes because you accidentally swiped the screen while viewing the camera, especially when the camera is slow to react to the pan-tilt commands sent to it (not sure if it's communication delay or due to the app or the camera) which makes it very difficult to reset to the original pan-tilt position.

With the joystick there, it's kind of redundant to have another way of controlling the pan-tilt. It might be nice for someone, but having an option of enabling/disabling the gesture control will be nice for everyone.