Good and addictive game but some problems. 1. When you earn a new car, it automatically makes that new car your car so if you don't like it you have to change it. 2. You can't go back so it's extremely difficult to complete almost all of the levels. 3. We should get more gems based off our score + normal gems as well as get gems for completing the levels. Without this, it takes way too long to unlock a car. A decent-but-not-perfect game and a great timekiller but definitely has great potential.