Probably the most easiest way to install Android on an iPhone 2G/3G is via iPhoDroid, which we did cover previously. But the problem with it is; you should have a computer to run the whole process of installing Android on your iPhone 2G/3G. But thanks to Bootlace 2.1, you can now install Android 2.2.1 Froyo on your jailbroken iPhone without needing to connect it to any PC or Mac!