Apksigcopier is a tool for copying android APK signatures from a signed APK to an unsigned one (in order to verify reproducible builds). It can also be used to compare two APKs with different signatures. Its command-line tool offers four operations:

* copy signatures directly from a signed to an unsigned APK * extract signatures from a signed APK to a directory * patch previously extracted signatures onto an unsigned APK * compare two APKs with different signatures (requires apksigner)