Awful! This is the first all negative review that I have given. I have a galaxy s II with dual core processor and the. controls are so laggy that I couldn't keep the car on the track. The motion/tilt control did not work at all. If the controls did work well you still have only one track and that is a plain oval. You race against 2 other cars in a circle, pick how many laps and that's it. No upgrades, no career, just one race over and over. They do give you choice of car color and red not one of them. $5 wasted!