Fortunately voice AI models have gotten very good and very affordable - I generated about 50 popular public domain books and built a listening app around them.
The app is totally free, and it should have all the standard features of an audio app (speeding, reviews, ai transcripts, etc), and I also added in RSS so that you can listen to basically any podcast on it as well.
I'd love people to check it out and tell me what they think - and if there's a public domain book you wish had an audio edition, let me know and I can add it to the app!