The Google Play Store is rolling out the ability to auto-download games or apps that have been pre-registered by a user, when available. The feature was spotted in a teardown back in January.
Target API level requirements for Google Play apps - Play Console Help
Google Play Store starts letting users auto-download pre-registered apps and games - Neowin
Target API level requirements for Google Play apps - Play Console Help
How to Fix Google Play Store Not Working on Mobile Data
Mobile App Terms & Conditions Template - TermsFeed
Why does Google Play keep installing apps on its own? - Quora
Android Auto: How It Works and Why You Need It - Kelley Blue Book
5 Ways to Use the Google Play Store - wikiHow
Google Play Store v18.6.28 hints at automatically installing apps and games you pre-register for : r/Android