If you want the best graphics and storyline pick shrek but if you want an unblieble online racing game like mario kart pick cocoto.
Shrek Kart has more characters, more cars, more courses. I still prefer Cocoto, because it does a better job of creating a sense of speed, which for me translates into a more console-like experience. Also, keep in mind that Cocoto comes with fully functioning online kart racing; currently, Shrek has only WiFi/Bluetooth.
Cro Mag: 9 tracks, two characters, good graphics and very fun but can get old quickly with no real game modes Cocoto: great sense of speed, multiplayer, hard but once you finish you get those "Yes!" moments Crash: nice graphics, three modes (cup, time trial, story mode), very fun, lots of content Krazy Kart: Multiplayer (but nobody ever goes on), lots of content, two minigames, Konami name characters, very fun Shrek Kart: Huge amount of content, amazing graphics, slightly low sense of speed, long loading times, pretty fun Zombie Karts: Good graphics, three characters, nice music, halloween themed, slow sense of speed Cro Mag: 8/10 for nice graphics and fun but no real modes (pick-up and play) Cocoto: 8.5/10 multiplayer and nice sense of speed and good gameplay Crash: 9/10 long lasting game, probably "funnest" out of these Krazy Kart: 9/10 great blocky looking graphics, very fun, soon will be additional content packs Shrek Kart: 8.5/10 amazing graphics and a huge amount of content but low sense of speed so if you want speed go for Cocoto Zombie Karts: 7.5 or 8 nice graphics, many updates, halloween themed, awesome music, fun
I'm not sure which one of these is the best, as I don't own any of them. However, it would be nice to see Mod Nation Racers come to the iphone / ipod touch. I think it would knock them all out of the box.
