Build an offline-first audiobook player that records a timestamped listening history and creates automatic restore points whenever playback pauses, chapters change, or devices synchronize. Start with locally stored, user-owned audiobooks and Audiobookshelf libraries, adding simple folder import, reliable chapter handling, and an interface for restoring any recent position. Sell the complete player as a one-time purchase, with an optional paid synchronization service.

Listeners increasingly combine downloaded files, self-hosted libraries, phones, tablets, and vehicle playback, while incumbent apps continue to lose progress during synchronization and updates. The evidence also shows willingness to pay a modest one-time price for a dependable, subscription-free player.