I run a few groups, like @fediversenews@venera.social, mostly on Friendica. It’s okay, but Friendica resembles Facebook Groups more than Reddit. I also like the moderation options that Lemmy has.
Currently, I’m testing jerboa, which is an Android client for Lemmy. It’s in alpha, has a few hiccups, but it’s coming along nicely.
Personally, I hope the #RedditMigration sours adoption of more Fediverse server software. And I hope Mastodon users continue to interact with Lemmy and Kbin.
All that said, as a mod of a Reddit community (r/Sizz) I somewhat regret giving Reddit all that content. They have nerve charging so much for API access!
Hopefully, we can build a better version of social media that focuses on protocols, not platforms.
From what it looks like to me in testing, in any given instance All is any other instance that communicates with said instance, Local is all communities within an instance, and Subscribed is just the communities within the instance you have explicitly subscribed to.