You can use APKUpdater instead, it supports APKMirror, Aptoide, F-Droid, IzzyOnDroid, APKPure, GitLab and GitHub, I tried Obtainium and it was PITA to set up, I am much happier with APKUpdater for apps not covered by Aurora Store

https://github.com/rumboalla/apkupdater

https://apps.obtainium.imranr.dev/ has plenty of apps that don't have F-Droid releases. Many of them come from the developers own website.

And if you see anything is missing, you can always add it!

The other way is to use fdroid as source within obtainium. The benefit is to maintain app list at one place, so you can export/import to another device, when needed.

You can use it with non-github releases too, but it's super rare when one isn't available. In the case when Obtanium doesn't work, I just use F-Droid.

Super rare? The government seems to release only on an obscure source called Play for some reason. I don't want to play a game, just to ride the transit system. There seem to be a lot of apps that don't release on such an addable source..

I think I’ve encountered 1 or 2 apps that didn’t work on Obtanium so YMMV.