Last December, Google announced a change to APKs uploaded to the Play Store that would insert a bit of security metadata in order to verify the provenance of these files. The "distributed by Google Play" metadata was made official this June, and although there was a lot of uproar about it being akin to DRM, the truth was a little far from that. Now, the Android Developers blog has announced the fruits of this whole ordeal: Play-sanctioned peer-to-peer app sharing is a reality.
Thanks to that metadata, Google Play can tell when an app that's been shared from another device (via an approved channel) is what it says it is or not. That authenticity can even be determined offline without requiring Play Protect or any other scan. Apps that are approved will show up in the Play Store and will receive official updates from then on. Basically, this would make sideloading even more secure. Currently, the first sharing channel supported is SHAREit, but Files Go and Xender should follow in the coming weeks.
Peer-to-peer sharing is handy in places where data networks aren't widespread and mobile data isn't cheap. App and game sizes are getting exponentially bigger, so being able to download once and share with all your friends and family is a handy feature, and could make all the difference between a game being played by one person or by an entire group.
Google says this should benefit both users and developers — the former because they'll have access to more secure software without needing to download it first, and the latter because without doing anything, they can now reach a larger userbase.
- Android Developers