Want to see 3D stuff without those special eyewear or special screen? i3D is one app you can count on, provided you have an iOS device with front-facing camera (iPad 2, iPhone 4, iPod Touch 4th Gen).
You see, this app is using a technology known as Head-Coupled Perspective (HCP), It uses the front facing camera to track the movements of a user’s head, allowing the app to adjust the display accordingly.
It is free to download on Apple App Store.
Here is the video to show you how it looks like.
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