Smart AudioBook Player (Android) https://play.google.com/store/apps/details?id=ak.alizandro.smartaudiobookplayer&hl=en_US&gl=US
I primarley use it in combination with google wavenet/ Elevenlabs to generate audio books from light novels (for personal use)
Biggest reason I like it is wavenet/eleven labs tends to generate 1-2 min mp3 files. Smart audio book allows clustering of these mp3 files (merging total listening time).