https://arstechnica.com/gadgets/2022/04/google-play-crackdown-makes-amazon-barnes-noble-pull-digital-purchases/

The great Google Play billing crackdown is finally here.

Developers selling digital goods inside their Android apps all need to switch to Google Play billing, or they will be locked out of the Play Store. This has technically always been the rule at Google Play, but it went mostly unenforced until Google gave developers a deadline of September 2021 to get on board. The company then delayed the transition by letting app developers request a six-month extension, which ran out on March 31. So it has been a few days now—what's different?