Project spotlight

Gnusto gives personal audiobook libraries a proper home on iOS

Gnusto is an audiobook manager and player focused on M4B files, fast import, reliable chapter-aware playback, smooth seeking, restartable sleep timers, variable speed, and robust progress tracking. It is designed for privacy and offline use, with library data kept under the listener's control.

App Store Download Support Privacy

App promise

Treat audiobooks as long-form personal media: organized by author, genre, narrator, chapter, and progress, with the controls listeners need when they return to a book days or weeks later.

Overview

A local-first home for personal audiobook libraries

Import M4B files from device storage, preserve embedded metadata and chapters, then browse by genre, author, and narrator without depending on an external server.

Playback and library navigation work together: bookmarks, progress tracking, chapter context, backups, restore options, and offload state are all part of the local library rather than afterthoughts.

Features

Core playback and local library features

Reliable playback Chapter-aware playback with precise seeking, variable speed, sleep timer, and reliable resume across sessions.
Library management Fast browsing, flexible views, sorting, and quick import of M4B files.
Search Instant in-library search across titles, authors, chapter titles, and book descriptions when available.
Bookmarks Local bookmarks and named positions with easy navigation and bookmark lists.
Offload and space optimization Remove audio files to free device space while preserving metadata, bookmarks, and listening progress.
Metadata and chapters Preserve and display embedded metadata, chapter markers, and table-of-contents for accurate navigation.
Editable book data Edit titles, authors, narrators, descriptions, genres, and cover images directly in the app.
Backups and restore Back up and restore library metadata, bookmarks, settings, and progress to iCloud or local files.
Personalization Adjust layouts, cover sizing, filters, grouping, and shortcuts to match how you prefer to listen and discover.
Shuffle listening mode Chapter-random playback for anthologies, short story collections, poetry, and other non-linear listening.
Diagnostics and support Activity logging and diagnostic log export to help troubleshoot issues.
iOS native experience Built with SwiftUI and optimized for iPhone-class listening with system media integration.

Coming soon

Planned improvements for listening, discovery, and library care

The next wave of Gnusto work focuses on better playback contexts, richer library management, and easier ways to discover or tidy long-form audio.

Listening

CarPlay and iPad

In-car controls plus an optimized iPad interface with multi-column browsing and larger playback controls.

Continuity

Optional iCloud Sync

Keep library state, bookmarks, and progress consistent across devices when you choose to sync.

Organization

Tags and Home

Advanced tag editing, bulk tagging, smart filters, pinned collections, and recent-listening widgets.

Metadata

AI Cleanup

AI-assisted cover art and metadata generation to make imported books easier to browse.

Discovery

Public Domain

Librivox and Internet Archive integrations for finding and importing public-domain audiobooks.

Importing

M4B and Podcasts

Write edited metadata back to M4B files and collect related podcast episodes as custom audiobooks.

Support

For Gnusto support, questions, bug reports, or help with diagnostics, contact support@ducat.dev.

If you are reporting a playback, import, backup, or library issue, include the app version, iOS version, device model, and any exported diagnostic logs you choose to share.

Privacy Policy

Effective March 1, 2026

Gnusto is designed to respect your privacy and keep your listening data under your control. The app is built around local ownership, no selling or sharing, and optional exports or backups that you initiate.

Stored on device

What Gnusto Stores

Library metadata needed for browsing and playback.
Listening state such as progress, chapter context, and playback preferences.
Bookmarks, user settings, tags, and custom playlists.
Downloaded audio files and related local indexes when you save content on device.
Offload state so metadata and progress remain after audio files are removed.
Diagnostic logs used for troubleshooting and reliability improvements.

Used for the app

How Data Is Used

To provide playback, resume, filtering, organization, and other core app functions.
To support optional backups and exports you initiate.
To support optional diagnostics and log export features you trigger.

Your backups

Local Storage and Backups

Gnusto is designed to work entirely on device. You can back up or export your library, settings, bookmarks, and progress to iCloud or to files you manage yourself. The app supports offloading audio while preserving metadata and listening state so you can restore, relink, or re-download audio later.

No selling or sharing

The Privacy Promise

Gnusto does not sell or share your personal data. Any movement of data happens only when you explicitly choose it, such as creating a backup or exporting files.

Your choices

User Control

You can choose local-only usage at any time.
You can remove downloaded content from the device.
You can export activity logs when needed for support.

Security

Security Notes

You are responsible for securing cloud accounts, backup locations, and exported files you use with Gnusto.
You are also responsible for securing any activity logs you generate and share, as logs may include library-specific data.

If you have questions or concerns regarding your privacy, contact support@ducat.dev.

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