The requirement to use in-app billing systems from app stores has come under heavy scrutiny over the past couple of years, and in that time Google has actually cracked down on some long-standing loopholes. Now, Amazon Audible and Barnes & Noble Nook have lost the ability to handle in-app purchases on Android over Google’s crackdown.

For safety reasons, Android Auto’s third-party apps are limited to those that playback media from your phone. At that, they share a pretty consistent user interface. Yesterday, an update to the Audible app added an Android Auto component and other playback features.