Updates for non-PlayStore apps

Does somebody know what happens with apps which are not downloaded from Google? I assumed I would have to take care of updating manually. But I noticed that if they are available via Google, they are detected to be installed and I can open them from the PlayStore. Does that by any chance mean that they will also receive updates from there?

(FYI, if you want to try out, the GuardianProject apps are usually available via different sources, including the PlayStore.)

Just try it. If the developer signed the playstore version of the application you want to update with the same key as the version you already have, the update will be installed, otherwise it won’t.


F-Droid also detects updateable apps (only if they are available in the F-Droid repository).
And e.g. Whatsapp, if you download it from their own webpage, updates itself, independently from Google.