The first game to take advantage of the iPhone 4's gyroscope has dropped: Ngmoco's new game Eliminate: Gun Range.
It is just a simple shooter but there is a ton of potential here. The gyroscope adds what seems like nearly 1:1 motion control to the gameplay, and since you're moving the display itself, it almost makes it feel like augmented reality. It's a unique mobile UI experience. The possibilities of games like this seems, endless and it's definitely something you have to experience.
The gyroscope will add huge improvements to actual augmented reality apps like Layar, and generate all kinds of crazy flight simulator games, much more refined GPS apps, etc., you name it.
Eliminate:GunRange $ 0.99 in the Apple iTunes store
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Check out Gyro Air Drums
http://itunes.apple.com/app/gyro-air-drums/id383027843?mt=8