Title - Lemmy

Meh, I'm happy to support the dev. No judgment if you don't want to pay, but I think it's worth it.
You can support FOSS devs, too.
When there’s a FOSS app as good as sync, sure.

Honestly, there are three right now on Android.

Thunder Connect Liftoff

I’m currently using Liftoff more than the others, but every week I’m seeing huge positive changes being made to all of these. Jerboa is an honorable mention, as I don’t think we can log in to that yet.

Thunder for Lemmy - Apps on Google Play

Thunder is an open source, cross-platform Lemmy client

Maybe I’m misunderstanding you, but I’ve never had any trouble logging into Jerboa. It’d be my favorite app but it has framerate issues on my device, so I’m using Thunder.