Archiving is a new functionality that will allow users to reclaim ~60% of app storage temporarily by removing parts of the app rather than uninstalling it completely. An archived app will remain on the device and can easily be restored to the latest available compatible version, whilst preserving the user data.
Google will do so by creating a new type of APK file, which it is calling as archived APK. These archived APKs will be comparatively much smaller than regular APKs, and will continue to store user data until a user decides to restore the app back to its original version. Google says that the archived APKs are “very small APKs” which are able to retain user data until the app is restored. Google, however, clears that even though the archived APKs are already under development, they won’t be functional until “the archiving functionality is launched to consumers later in the year.”
Once the archived APKs are generated, they will be made available to the developers for inspection through Generated APKs API or in Play Console under App Bundle Explorer. Interestingly, Google has made the archived apps functionality open source. This will allow developers to inspect the code, and even other app stores to make use of it with a few altercations.