I have just purchased a 2017 A6 sline that has the tech pack option. So it has the bigger mmi screen, DIS and wireless phone charger in the arm rest. I queried Apple Car Play / Android Auto. It is a retrofit software update option that the dealer can do. All MY2017 cars with the tech pack could have had this optioned from factory and in my case retrofitted. I have copied the Web link to Audi's official accessories page that should explain more. Prices do vary from dealer to deal. Would be looking at £350 ish. Takes the dealer about 30 mins to action the update.
https://shops.audi.com/en_GB/web/zubehoer/p/retrofit-solution-for-the-audi-smartphone-interface-4m0051472-9?category=8047:904_ASOS:Category
