I'll develop an audiobook player application turnkey

I develop mobile audiobook player applications from scratch, based on real listening habits: on the road, while jogging, before sleep. Every project is built around four functions without which listening to an audiobook is inconvenient. These are automatic remembering of playback position separately for each book in the library, changing playback speed without distorting the narrator's voice timbre, a sleep timer with smooth fade-out and automatic stop, and bookmarks to mark the right moment and return to it in one tap.

I handle the full cycle: interface design, development for iOS and Android, integration with your catalog and audio formats, testing on real devices before release. Speech acceleration is implemented through pitch correction algorithms, not simple speed multiplication — when speeding up by one and a half or two times, the narrator's voice sounds natural, without squeaking or crackling. Position is saved separately for each book and survives app restarts, updates and reinstalls, if you add cloud synchronization.

Additionally I include: downloading books offline, chapter navigation, sleep timer presets, night mode, and library list with progress indicator. I transfer the source code upon project completion so the application remains fully yours.