I was looking for a place to share my two favorite Mastodon and Lemmy clients, they are called Voyager Connect Boost for Lemmy and Moshidon for Mastodon (if you are really serious about privacy I recommend Connect still)
(the official Mastodon app works fine though, you just can’t follow new hashtags from it)
They are very good, try them out sometime 👍 (I’ll update this post whenever my opinion changes)
Liftoff is available on iOS too! It’s probably the exact same app, but I find the interface a bit too cluttered for my tastes. But it is packed with features!