After you've made a flight of stairs (up to your house, for example) if you walk to the top of them at the last step you jump up randomly. I think this is because you are touching the screen to guide the player.

So if you go up, just touching the forward button and only that, you walk normally off the stairs. But if you hold the forward button AND use the other hand to steer steve, when you get to the top of the stairs you jump. Its just annoying.

Thanks