Developer Nick Lee designed and built a 3D-printed case that lets Android run on an iPhone. He did this by modifying the Android Open Source Project (AOSP) — specifically the Marshmallow source — to run on iOS hardware.
In an interview, Lee explained that the case itself is the key component — it provides the hardware layer that makes Android run on an iPhone. He spent many hours building it.
One interesting advantage of this setup is that you can switch between iOS and Android on a single device, effectively running two operating systems on one phone.
Lee also developed a series of ports on the case for HDMI, USB, and SD Card. Impressive work — looking forward to seeing more from his team.