I have been using it for a few hours now and I can see that it's still in quite early stages of development. For some reason it doesn't use system default tts on my tablet. A lot of the menus are laggy(on both android and linux desktop). Has very little options. No way to import a full folder. No opds support yet and no RSVP.
I will stick with Librera for now as it also just started getting maintenance recently.