The entity is in constant fall and the only way to reverse its movement is by tilting the device to one side or the other. But beware of blocks that can cause the entity to shrink, expand, slow down, speed up, reverse its motion, decrease and increase view.
It is advised you select the 'help' button within the game and read more about the blocks.
To pause within the game simply tap the screen.
Unlimited hours of fun, gameplayability.