This game has one of the best shop systems I've ever seen in an iOS game, and it's very addicting to play. Even though the gameplay is honestly somewhat repetitive (as it would be) I can tell a lot pf work was put into making a diverse environment, such as different kinds of obstacles and even different biomes (which don't really affect the game, but help heighten the mood). I found it to be a little too "pay-to-win" with characters that were kind of cheaply designed and didn't have much depth and the characters you had to buy were always better. As with all iOS games, there were things about it I found stupid, but it gives you a good 6 hours of gameplay, I'd say, before it gets boring.
As others have noted, the gameplay gets very repetitive and very old quickly. After about two or three hours of playing the game, I lost interest. The levels also get insanely difficult once you reach about 2000 meters on each level – the speed becomes impossible to keep up with.
The only good things about this game are the graphics, music, and sound effects. Having the various different kinds of themed levels is also exciting, but that does absolutely nothing to lessen the repetitive gameplay.
Recommended if you have two hours or less to waste.