I'm new to Lemmy (refugee from Reddit) and I just sought out the Jerboa community to ask this exact question, so I'd love to know the answer to this too. Seems like a pretty obvious thing to want to do, so I'm surprised it seems to be missing (or just hard to find).
If you sign into your insurance on PC, I've been able to browse communities of all instances and subscribe. In the app, the only thing I can figure out how to do is search for what I'm looking for (it does search all instances) and subscribe when I get there.
Jerboa is a native-android client for Lemmy, built using the native android framework, Jetpack Compose.
Warning: You can submit issues, but between Lemmy and lemmy-ui, I probably won't have too much time to work on them. Learn jetpack compose like I did if you want to help make this app better.
Jerboa is made by Lemmy's developers, and is free, open-source software, meaning no advertising, monetizing, or venture capital, ever. Your donations directly support full-time development of the project.
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