I really enjoyed Libro.fm, it works the same as Audible but you can either use their app or download the book files, and I think they’re DRM free.
Also it’s really cool because you get to choose a local book store to support and I think they share a part of what you spend with them.
You just made me realize I say “I have no strong feelings one way or the other” a lot and I think usually people don’t know I’m quoting anything.