One app for your music, wherever it lives.
A free, open-source player for the Plex, Jellyfin, or Subsonic server you already run.
Mozz plays the music that lives on your own media server. Point it at Plex, Jellyfin, or a Subsonic / OpenSubsonic server (tested against Navidrome) and your whole library shows up on your iPhone and iPad — ready to stream over the network or download and take with you.
Streaming and offline both matter here, equally. Some people stream everything and never download a thing; others save their library and live underground on the subway. Mozz is built for both, and it does not push you toward either.
One app for your music, wherever it lives. Free forever. Open source.
You already self-host your music — on Plex, Jellyfin, Navidrome, or another Subsonic-compatible server — and you want a fast, native iPhone and iPad player that respects it: no second subscription, no re-uploading your library to someone else's cloud, and no telemetry watching what you listen to.
- Bring your own server. Connect Plex, Jellyfin, or Subsonic/OpenSubsonic and sign in the normal way for each — a Plex login, Jellyfin Quick Connect or password, or a Subsonic account. Choose exactly which libraries to pull in.
- One tidy library. Artists, albums, songs, playlists, and genres all live in one place, however your server organizes them.
- Works when the network doesn't. Your catalog is kept on the device, so browsing, searching, and opening albums stay instant even when the server is slow, far away, or offline.
- Search that keeps up. Results appear as you type, and accents and punctuation don't get in the way — "bjork" finds "Björk".
- Near-gapless. Tracks flow into one another without a silent gap between them, the way an album is meant to play.
- Smart shuffle. Shuffle spreads your artists out instead of clumping the same one back to back, plus the usual repeat modes.
- Even loudness. Volume normalization keeps quiet and loud tracks at a comfortable level, so you're not reaching for the volume between songs.
- A real equalizer. A 10-band graphic EQ (31 Hz–16 kHz) with presets, for when you want to shape the sound.
- Lyrics. Time-synced lyrics that highlight and scroll the current line, with a full-screen mode for just the words. Mozz uses your server's lyrics first and falls back to LRCLIB when there are none.
- A player that flows. Now Playing glides between a small bar above the tabs and the full-screen player — no jarring pop-up. Scrub, reorder what's up next, or tap through to the artist or album.
- Download for the road. Save albums, playlists, or tracks to the device and play them straight from storage — no network needed, no quality loss.
- Downloads that stick around. Transfers keep going while the app is in the background, and re-syncing your library never loses what you've already saved.
- Lyrics come too. Saved lyrics travel with your downloads, so they're there when you're offline.
- Continue here. Leave off on one device and Mozz can offer to pick playback up where you left it on another — resumed only when you choose, never yanked away.
- Handoff & deep links. Hand a screen off between your Apple devices, and
mozz://links open straight to an album, artist, playlist, genre, or tab. - Sign in once. Your server credentials travel between your own devices through the iCloud Keychain, so you don't retype them.
- Ask for anything. "Play …" a song, album, artist, playlist, genre, your liked songs, or a mix — from the Siri button, Shortcuts, or a HomePod, which hands the request to your iPhone and plays it back through the speaker.
- CarPlay. Your Home and Library on the car screen, with artwork, a shuffle shortcut, and an Up Next list. It reads the on-device library, so it stays quick where signal is poor and downloaded tracks keep playing when the server can't be reached.
- Widgets. Now Playing and Recently Played widgets for your Home Screen.
- Mozz Weekly. A weekly mix that rediscovers music already in your library, built right on the device.
- Radio and mixes seeded from what you're listening to.
- Optional enrichment. Turn it on to sharpen radio and mixes using open music databases (only song and artist names are sent); leave it off and recommendations stay entirely on your device.
- Likes and stars, unified. Jellyfin and Subsonic favourites and Plex's star ratings show up together as likes and ratings, and Mozz writes them back to your server where it's supported.
- Themes & appearance. Light, dark, or follow the system, with a choice of dark looks and an optional Liquid Glass player finish on newer iOS.
A companion Mozz Desktop app for Windows, macOS, and Linux shares the same
library, history, and taste as the phone. It's early and distributed as a build you
download rather than through an app store — see
clients/desktop/README.md.
- iPhone or iPad running iOS / iPadOS 17 or later.
- A media server you can reach: Plex, Jellyfin, or Subsonic / OpenSubsonic. Navidrome is the tested Subsonic target; other OpenSubsonic servers are best-effort.
- Install Mozz on your iPhone or iPad (see building it yourself below while a public release is in progress).
- Open the app and choose your server type — Plex, Jellyfin, or Subsonic.
- Sign in the way that server expects and pick the libraries you want.
- Wait for your library to appear, then start streaming — or download some albums for offline.
Mozz has no backend of its own and collects nothing about you — no account, no
analytics, no tracking. It talks to your media server, to Plex's sign-in and
discovery service when you use Plex, and — only when you turn those features on — to
LRCLIB for lyrics and open music databases for recommendations, sending only the
minimum needed (song and artist names). Full details are in
docs/PRIVACY.md.
Found a bug or have an idea? Please open an issue on GitHub Issues. Clear steps to reproduce, your server type, and what you expected all help.
Mozz is open source and contributions are welcome. Build instructions, the code
layout, testing, and how releases work live in
CONTRIBUTING.md; the deeper design rationale is in
ARCHITECTURE.md and the notes and decision records under
docs/.
Mozz is free forever. If it's earned a place on your Home Screen and you'd like to chip in, you can sponsor development through GitHub Sponsors. It genuinely helps — but not donating is completely fine, and you get every feature either way.
Mozz is free software licensed under the GNU General Public License v3.0, with an
additional permission under section 7 allowing distribution through Apple's App Store
despite its DRM and code-signing requirements. See LICENSE for the full
terms.
Mozz is not affiliated with or endorsed by Plex, Jellyfin, Navidrome, Subsonic/OpenSubsonic, MusicBrainz, ListenBrainz, or LRCLIB. All trademarks belong to their respective owners.
More open source
