“Grav” is an awesome game, and it is very addicting. The basic premise is that there is a ball that obeys the normal laws of gravity and inertia, but there are different tiles that influence the game. There are tiles that push the ball away from them, tiles that bump the ball away, and spiked tiles to avoid. The large variety and the 110 progressively more difficult levels make it a very addicting game, a combination of puzzle, strategy, and reflex.