ModJoy and Package Signatures: A Beginner’s Guide for Android Users

https://apkgameselect.urbanvellum.com/posts/7-things-to-check-about-version-rollbacks-before-using-joy-apk-game-2

A package signature is a digital identity used by Android to help confirm who signed an app and whether updates match. A beginner does not need to know every Android term before making a careful choice