Problem with pages being able to be moved around the screen on mobile devices

If you just look at the page it looks normal. The content fills the screen properly. But you can scroll past the top of the page and see a gray background. Similarly you can scroll down past the bottom of the page and see a gray background. The page will bounce back so the top or the bottom will move back in place, but you still scroll past the top and bottom. If you grab the page your finger and move it the right, you will see the same background on the left. If you let go, it bounces back in place. Same thing for if you move it to the left. How can I get my pages to not move around on mobile devices like that and stay in place? I think I'm still using version 1.3.41 premium.