iPhone · iPad · Mac · Android
Seaglass is a hands-on music player: beat-aware transitions, tempo control, synced lyrics and a library you can shape.
An unofficial, independent project: not affiliated with Google, YouTube, Spotify or Apple.
Your music, in motion Beta Premium
AutoMix analyses your songs and chooses a transition that suits them. When the rhythm allows, it lines up the beats by gliding the tempo gradually, without changing the pitch; when two songs don't suit each other it picks another kind of transition instead.
AutoMix is a beta feature: it works, but it is still being tuned, and some transitions may not sound right yet.
Beta Premium
Open a playlist of downloaded songs and shape each transition yourself, with waveforms to see exactly where the songs meet.
The playlist Mix is a beta feature too.
Premium
Speed a song up or slow it down by up to 15% (or 8, 25, 50%) and see its BPM. Key lock keeps voices at their pitch; switch it off and the pitch moves with the tempo, as on a turntable.
iPhone, iPad and Mac.
Drag the slider
Premium
Synced lyrics scroll with the song and jump to a line when you tap it. Translate them with on-device tools, and let AI karaoke take the voice out of the song: it all happens on your device.
Choose the audio quality for Wi-Fi, mobile data and downloads. Maximum quality can use Opus; Dolby Digital Plus or AAC when they're available. The format depends on the song and your device.
An illustration: the presets in the app differ.
Everything you'd expect from a music app, and a few things you wouldn't.
Songs, albums and playlists for offline listening, with storage usage in settings.
Choose a folder on your device and its MP3, M4A, FLAC, WAV and AIFF files play where they are, with the queue, playlists, AutoMix and karaoke.
iPhone & iPadBring them from Spotify, Apple Music and YouTube links or files, then review what couldn't be matched.
Swipe a song right to add it to the queue; hold it for more options.
iPhone & iPadRadio stations and personalised mixes from the YouTube Music catalogue.
Follow shows, pick up each episode where you left it, change the speed, skip 15 or 30 seconds and jump between chapters.
Connect Last.fm to scrobble what you play and get more from your listening.
Tap to identify what's playing nearby, then save it to your favourites, downloads or a playlist.
iPhone, iPad & MacAn optional Seaglass account keeps favourites, playlists, history and listening preferences the same on iPhone, iPad and Mac.
iPhone, iPad & MacThe same catalogue and the same ideas on the phone in your pocket, the tablet, the Mac and Android.
iOS 26 or later, and iPadOS 26 or later with a layout of its own. Every feature on this page, in a design built for Liquid Glass.
Laid out like Apple Music on the Mac: the sidebar with your library and playlists, the player bar along the bottom and the player in glass. Closing the window keeps the music playing, with Seaglass's note in the menu bar, and updates install themselves. Needs Apple silicon and macOS 26 or later.
Android 10 or later, with liquid glass on Android 13 and later. AutoMix (beta), crossfade, an equaliser with Spotify's 22 presets, AI karaoke, lyrics with translation, downloads and a sleep timer. It is a younger app (0.x) that grows with each release.
Screenshots from the simulators. Artwork, names and music belong to their rights holders.
The interface follows your device's language.
Seaglass isn't on the App Store or Google Play: it comes straight from GitHub.
iOS or iPadOS 26 or later. The IPA is unsigned: sign and install it with Sideloadly, AltStore Classic or SideStore.
Add Seaglass's source once, then install and update from AltStore.
https://raw.githubusercontent.com/Foglio24/onda/main/altstore-source.json
A Mac with Apple silicon (M1 or later) on macOS 26 Tahoe or later.
Android 10 or later.
It's new and still being tuned on many kinds of music: the choice of transition and its timing can still be off for some songs. The playlist Mix is the same. They improve with every version.
No. It favours transitions in time when they suit the songs, but picks another transition when their rhythms or vocals would make a mix sound wrong.
What's available varies by song. The app may use another format, for example when Dolby is available or Opus can't be decoded. The player shows the format, and the settings have diagnostics.
Some recordings can't be found or matched with enough confidence. The import report lists them and offers alternatives. For long Spotify playlists, import a JSON or CSV file.
Open an issue on GitHub with your app version, your device and the steps to reproduce it. Settings → Diagnostics can build a report.