This game is great. I played it, and beat the main story on my iPhone. I enjoyed it so much, I decided to start over again on my Mac. The reason it got three stars is because it did not adapt at all from the iPhone to the Mac. It easily would have gotten five stars if the developers would have allowed the player to change gears and rev up on the keyboard instead of having to use the mouse for everything. I know I’ve slipped a few gears going from my nitro back to the gear up.