

If you’re looking for free, I would suggest OpenLibrary, which has an android app: https://openlibrary.org/
I will say that the app/site is not fun to use. It’s not intuitive and very poor in it’s “rental” process.
Since I have an Amazon Prime account, I most often read books available for free that are included with Prime.





Sorry, I should have linked it: https://play.google.com/store/apps/details?id=com.loomishouse.ol_reader_app
I think the 3.5 rating is generous but its technically usable.