raspberry pi based head unit running crankshaft for Android auto I made. still got a few things to work out mainly on the volume control but other than that it works perfect :
Add Android Auto to Your Car with a Raspberry Pi and Touchscreen - Hackster.io
Post your setup! : r/crankshaft
RaspberryPi, Android or Crankshaft | Volkswagen Golf MK2 | on-board computer | Part 2