yes, but it’s mostly for open source apks, the beauty of apkupdater is that it allows installing/upgrading some apks from apkpure and other sources (it was true for apkmirror directing to the right place to download and install from the browser, but on apkmirror most apks now days don’t install/upgrade unless you install their own apkmirror app), avoiding google play and avoiding aurora store (which besides the issues with anonymous connections, it gets upgrades pretty late for some reason). That’s something I don’t see an alternative for. Yes, upkupdater also allowed to install/upgrade from github/gitlab/… but its major purpose to me, was to be able to install/upgrade some non open source stuff without the need to connect to google play, and using recognized and reputable mirrors like apkpure and when it was feasible apkmirror. For FLOSS I use f-droid (official repo, plus non official like “izzyondroid” and others). Unfortunately there are a few apps I’m forced to use, which are not open source…

If ever getting to administrate non systemd boxes, and in need to deal with the system logging mechanism, then syslog-ng comes close to the most probable mechanism use. And no, non systemd gnu+linux distributions are not legacy, there are quite a few out there, just not the major or mainstream ones, like Artix, Void, Guix, and several others, not to count non gnu+linux OSs like BSDs…