Like there is the Official Mastodon app for Mastodon, and Element app for Matrix, which app is considered the most official lemmy app for Android [possibly also for ios]
Or atleast, the app which supports most(if not all) the features available in Lemmy
Connect isn’t bad. They can’t seem to get blur right (currently must have “NSFW” stamped on it) and sometimes a refresh causes some kind of weird looping of content, but beyond that it’s stable and had good features.