4 stars: Very fun sonic game which has various events to unlock characters. The only issue I am having is with ads which sometimes don't load with video or sound and there is no way to know when they are finished. I have had to force close the app many times because I was unable to proceed.
2 stars: Fun game, good for killing time: but rarely gives notification when being attacked from behind, calculations are off on points and is annoying that if you're in 1st place it doesn't allow you to get more speed in which case it's easy for others to blow past you... The upgrade suck, the game freezes a lot and you end up losing
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