Since a lot of you asked me to build an Android version and post about it here when I launch, and I sincerely apologise that I forgot to post on lemmy sooner. The free app was launched on Play store almost a month ago and has garnered some excellent reviews.
It has feature parity with the iPhone App and works on all Android 8.0+ devices.
I suggest arrows to navigate main comments (I think they also call them "parent comments" or something). As an example, Sync for Lemmy and Now for Reddit have them.