I've just got a P4, my first phantom. I've read a lot of info and watched a lot of tutorials and had a good first few flights. Today though when I went to try active track I had an issue. When I tap on the screen to drag the square over people, the tap just changes the camera's position. I then tried tap to fly, and again tapping just served to move the gimbal. I'm pretty sure I've just changed some setting by mistake, but I can't figure out what it is. Any clues would be gratefully received!