Asphalt 8: Airborne is the most recent addition to the Asphalt franchise of racing games. It's a fantastic racing game with a diverse lineup of cars and tracks. You can play single player races or race online against other people. Perhaps the greatest feature of the game is its graphics, which are top of the line for smartphones. Unfortunately, that means that owners of an older smartphone or one without a powerful CPU will find themselves dealing with lag and performance issues. It's a fantastic mobile game nonetheless.
The Asphalt series has been one of the best tablet racing games, the graphics are simply amazing. However it seems that the developers are running out of new innovation to introduce into the series, and are resorting into ludicrous scenarios like airborne racing. Personally I liked it better when the degree of realism was stronger. Still, it's probably one of the best free games available on tablets.