What you can do is jailbreak your iPhone and install iDroid, an Android-like OS made for iPhones. But you cannot install Android itself on an iPhone.

In conclusion, iPhodroid offers a more accessible way to install Android on your iPhone, making it easier for users to explore the Android operating system without needing extensive technical ...

Apple has released the iPhone OS 2.0 update for first-generation iPhones. Once the new software/firmware is installed, these devices can access the AppStore. In order to apply the iPhone OS 2.0 ...