Android Auto-compatible head units aren't too difficult to find these days, but they cost a pretty penny and usually won't fit properly in older cars. A developer created a solution called Crankshaft to address both of those issues, and all you need to make it a reality is a Raspberry Pi 3 and a touchscreen. Read More
When Android Auto was first introduced, your only option for using it was to buy a brand new car. But soon enough, third-party head units (like the lovely Sony one pictured above) started showing up. Now that you can run the full Android Auto interface on your phone, you don't strictly need a compatible head unit, but they're getting cheaper anyways.
Now you can get the Sony XAV-AX100 and XAV-AX200 head units for $50 off the usual prices. Read More