There’s plenty of work that goes into something like this, but for the folks out there that are interested in the finer details on how to get it to work, Lee went into great detail right here. The condensed version is that Lee made a 3D-printed case, put a single-board computer in it, with a battery, and then used the Android Open Source Project (AOSP) to get Android 6.0.1 Marshmallow running on an iPhone.
The iPhone connects to the computer through USB, and the 3D-printed case has seen plenty of revisions down to its current state, which is about the size of a standard battery case. Except this case also features a microSD card slot, and ports for HDMI and USB. There’s also a 650mAh battery to power the computer.
The result, once the iPhone is slotted into the case and plugged in, is Android on an iPhone. Lee just has to launch the Tendigi app on the iPhone and there’s the Android user interface. Unfortunately the touch responsiveness isn’t fantastic, and there are some pretty bold black bars at the top and bottom of the screen, but otherwise it’s Android running on an iPhone.
Check it in action:
So what do you think about this idea?
[Source]