I'm an avid kart racing fan. I have tons of console kart racing games, and enjoy almost all of them. So, at the release of the App Store, I immediately had to get Crash Kart. Then, when Krazy Kart came out, I absolutely had to get that too. Then, when Cocoto Kart came out, I knew I had to add it to my collection. So, I now have all of the quality kart racing games in the App Store, and what do I do? I compare them, so you can choose which one fits you the best, and give you an in-depth description of each individual game.
First off, Crash Bandicoot Nitro Kart 3D, now $2.99. ($5.99 at launch) This is the first of the kart racers, and it shows when playing the game. As you play through the 12 tracks, with one of 8 different characters, the frame rate is low, and the graphics look outdated. (Unless you're on an iPhone 3GS, or iPod Touch 3G, then the framerate is fine, but the graphics are still bad) The tracks have good designs, but without any difficulty levels, you can finish the game in an hour. The 8 power-ups are good, but are exactly the same as Mario Kart for consoles, but with different skins. (Which isn't necessarily bad) Vivendi tries to incorporate missions, but "finish in front of that guy" missions aren't exactly very different from the main mode. To control the game, you can tilt the device, and tap a corner of the screen when you get a power-up.
Pros:
Good Track Design
Relatively Fun
Crash Bandicoot Characters
Cons:
So-so graphics
Short, even for the low price
No multiplayer
The second kart racer released, Krazy Kart Racers, now $7.99, is a huge improvement over Crash Kart. It has 16 tracks, 10 characters, 5 single-player modes, and 3 difficulty levels. Strangely, even though Metal Gear Solid is Konami's biggest franchise, they decided not to include a character from it. The graphics in Krazy Kart are close to the level of Mario Kart DS's graphics. (Blocky, but very good looking) The frame rate is good, and looks amazing on a newer device. The track design is boring at first, but then gets more interesting as you play through the game. To control your character, you can either tilt or use a slider. There is always auto-acceleration. Even though the game is very good, there isn't enough content to justify the $7.99 price point.
Because of the lack of buyers, even though there is worldwide online multiplayer, no one is ever online. If you want to play somebody, you have to go through a confusing process, then just wait until somebody comes. Sometimes the multiplayer makes the game crash, which is even more annoying. If you succeed in starting a multiplayer match, the older devices have a disadvantage, because the newer ones load so much faster that their countdown starts a second early.
Pros:
Very fun
Cute, great graphics
Tons of content
Cons:
Multiplayer doesn't work like it should
Too expensive
Sometimes randomly crashes
Last, but not least, Cocoto Kart Online. Cocoto Kart is the bargain kart racer, priced at $.99. It has 10 tracks, and 5 battle mode maps. There are also 12 unique characters, each with slightly different speeds and handling. Out of all of the kart racers, this is the most similar to Mario Kart. It has two 5 track cups, which have 50 CC, 100 CC, and 150CC difficulties, plus Mirror Mode. Mirror Mode makes each track like a new level, and adds tons of replay value to the game. The cups are way too difficult, unless you are a master kart racer. However, if you learn the shortcuts in the maps, it becomes more fun to race, and easier to beat the CPU. There are four options to control. You can use two arrows with/without auto-acceleration, or tilting with/without auto-acceleration. The tilting isn't extremely accurate, and sharper turns can be done easier with the arrows. The frame rate is very good, and the graphics are in between the levels of Krazy Kart and Crash Kart. You view your kart from further behind than the other two games, which increases the sense of speed. Now, we come to the online multiplayer. That's what the game is really about! In this aspect, Cocoto Kart completely crushes the other games. Its multiplayer is fantastic, and includes a battle mode, and unlike Krazy Kart, where you have to wait in the lobby, you can go back and play whatever mode you want while you wait. However, you won't need to, because unless you play at some time in the middle of the night, there are always people on. (Even in the middle of the night, people across the world could still be playing) The interface is simple, and the servers always work, and seem to connect to eachother.
Pros:
Fun tracks + shortcuts
Good graphics
Amazing multiplayer
Cons:
Hard singleplayer
So-so tilting controls
Bottom Line- Which Kart Racing Game Should You Get?
Crash Kart is out of the question. It's completely inferior to Krazy Kart and Cocoto Kart. If you have the other two kart racing games, and want more, then try Crash Kart.
Krazy Kart's most impressive feature is multiplayer, yet it doesn't work very well, and the game is way too expensive. If you have lots of money, and want a lot of content, buy Krazy Kart.
Cocoto Kart is a steal, with fun tracks (and lots of shortcuts!) and incredibly good multiplayer. You should pick this up no matter what. Even if you don't like kart racers, Cocoto Kart could make you become a fan of the genre.
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EDIT: Eliminate is now out for free WORLDWIDE! 
