It's called Earleaf, and lets you play your local audibook files.
The feature I'm most excited about is Page Sync. You take a photo of a page in your physical book (or e-book) and the app finds that position in the audiobook and jumps to it. It works by transcribing the book on-device, and when you take a photo, it uses ML Kit to do the OCR scanning, and matches the text against the transcription. The initial transcription takes a while, but that's a one-time thing, and when it's in place, the actual search takes about two seconds on my device. And everything runs locally.
Aside from Page Sync, it's a full-featured player with nested collections, independent listen-through tracking, and a pretty good statistics feature. There are no accounts, no internet required, no ads.
Happy to answer questions about the app and its features!
