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)
For Lemmy sync and voyager, for mastodon I use elk.zone for both desktop and mobile