Amp

(A)nother (M)usic (P)layer, for the Light Phone III.

Plays your own library — a Subsonic server, Plex, or files on the phone — and is built on Light's SDK, so it looks like it belongs there.

Side-load only for now. The tool store isn't open yet.

For advanced users at this stage — installing means USB debugging and adb, and things will break.

Features

• Subsonic (Navidrome, Airsonic, Gonic), Plex, and/or local files on the phone.
• Bandcamp speaks Subsonic now, so you can use Amp without hosting anything.
• Offline downloads, by album, track, or everything you've liked.
• Data Mode: choose what happens off Wi-Fi. Nothing is silently downgraded. Defaults to WiFi Only, so on cellular it plays your downloads rather than streaming — change it in Settings if you'd rather it streamed.
• Synced lyrics.
• Play counts, ratings, likes and playlist edits sync back to the server.
• Cast to a DLNA speaker or receiver.
• Artwork can be turned off completely.

I use it as my only music player, on a library of about 8,000 tracks with 50GB downloaded.

Installing

USB debugging needs to be on: Settings → Developer options → Allow USB debugging. Then take the APK from Releases and either drop it on Light Phone Manager, or:

adb install -r amp-*.apk

Music on the phone

Amp reads Music/Amp, and nothing else.

adb push ~/Music/some-album "/sdcard/Music/Amp/"

Sub-folders are fine. Names come from the tags rather than the folders, and artwork has to be embedded in the files — a cover.jpg next to them won't show.

Playlists live in Music/Amp/Playlists as .m3u8, so one you make on the phone opens anywhere else, and one you drop in that folder shows up in Amp.

What isn't in the SDK yet

Four things sit outside the official SDK. Background audio and background downloads are the two that stop this being a plain SDK tool. Colour and DLNA casting are extras that would come out for a store build.

What each stands in for, and what would replace it, is in SDK gaps. The SDK changes themselves are listed with revert steps in SDK patches.

Colour is the only one you have to do anything about. It's off by default, and switching the phone's greyscale filter needs a one-time grant:

adb shell pm grant com.sublunar.amp android.permission.WRITE_SECURE_SETTINGS

Then turn off Settings → Monochrome Artwork.

Building

This repo is lightphone/light-sdk with the app in its tool/ module, which is the shape a LightOS tool takes.

./gradlew :tool:assembleRelease

Licence

MIT. The app is © Amp contributors; the rest is Light's SDK, © The Light Phone, carried here with our changes on top. See LICENSE.