Generally I don't use rsvp apps (I use a bog standard library app), however, when I get an epub book, I load it into an app called Librera Reader (Android) and that flashes text up quite nicely:
Links:
Interesting how neither their website nor their description mention the source-code. I hope they would at least mention it inside the app itself.
Answering my own question: after some research, I DEFINITIVELY suggest the Librera Reader, as it offers almost all of the things I was asking for in my question. Very nice library interface, quick lists to access recently opened or opened documents, quick navigation, global bookmarks etc. I am currently using it on my 11" tablet and it seems great for reading books. I have not used it in a live session yet (THANK YOU COVID!!!), and I do not think that I will totally replace all the books I have with me during a session, but it will be a great asset for all that "other stuff" I would like to have available at any given moment.
Librera lit presque tout (livres kindle et bd numériques aussi). C'est un logiciel libre, même si la version "sans pub" est payante sur le play store, tu peux la télécharger directement sur leur site https://librera.mobi/