https://www.gtacarkits.com/product/wireless-carplay-and-androidauto-integration-for-mercedes-c-class-glc-2015-2018/

How to install a kit that enables Wireless Apple CarPlay and AndroidAuto in Mercedes C-Class GLC 2015, 2016, 2017 and 2018 model years
The kit supports upgraded sound system for C-class and GLC.

List of Version 2 improvements:
- Wireless Android Auto is now supported
- no need for a separate microphone for Siri or Google Assistant, now works through the original car microphone