For example, https://pixelfed.de and https://pxlfd.me have done a pretty good job of staying up to date.
You might want to take a look at @pixelfed. It's almost ready for launch, you can already join on the beta instances (though they aren't federating yet).
The biggest instance is https://pixelfed.social but there's also https://pxlfd.me , https://pix.diaspodon.fr , https://pix.hostux.social and many others.
There's no app yet, but there's several in development including @morii
They've temporarily closed new registrations on pixelfed.social to encourage people to register on the other instances. You could try https://pxlfd.me or https://fedigram.social for example?
Interested in a Pixelfed t-shirt?
@Whaxion admin of https://pxlfd.me/ is running a poll to gauge interest in getting some made!
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