installation - (how) can I install android on an iphone 4?

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Closed 8 years ago.

Possible Duplicate:
Can I install Android on my non-Android device?

I know it is possible to install Android on an iPhone 3G.

How about the iPhone 4? Is it possible to run Android on it? If yes, how, and what are the risks?
If no, is that a "not yet" or a "can't happen, because of X"?