OEM Headunit retrofit for Android Auto
 

hey everybody I am trying to figure out what I can do to upgrade my OEM headunit to support Android Auto and still retain the OEM look.
I currently have a 2013 A7 Prestige that I absolutely love. In my previous vehicle I had an Android Auto compatible headunit and I used it all the time. I know the newer A7's have android auto built in but I am curious if I could do a retrofit into my car.

Has anyone looked into it, and what it may take to make it work?
Also what year did android auto become available in the A7?