Standalone Plex music playback for Android phones, tablets, TV, and Android Auto. Plex and access to a Plex Music library are required. Android 8.0 (API 26) or later.
Download the signed APK from the latest release. Install over the existing signed app to retain personal-mode settings and data. Choose Sign in with Plex, then your server and Music library. TV setup shows a QR code for Plex sign-in on your phone. Shared libraries support listening. The current development build also supports shared-library room hosting and paired native playback; Plex rating/history writes still require server owner access.
- Nocturne browsing/player UI with persistent Nocturne, Aurora, and Ember palettes.
- Albums, singles, EPs, artists, biographies, live search, and paged Plex playlists.
- Voice input through Android speech recognition and remote-friendly TV focus.
- Request-first queues, configurable automatic mix, adaptive ratings, and Track Radio.
- Android Auto library browsing, artwork grids, playback, thumbs up/down, and track ratings (controls may appear under More).
- Temporary nearby rooms, requests/votes, and bundled browser guest/display pages.
- Owner-controlled native room playback transfer and take-back.
- Optional Stay awake while charging while Harmonicast is open.
Rooms are for nearby guests. Native transfer needs a reachable local Wi-Fi/Ethernet network. Internet guest control is outside scope. Active Android Auto projection retains playback authority until disconnected. Track Radio depends on Plex support.
Settings has nine categories: Appearance, Playback, Equalizer, Automatic mix, Track Radio, Automatic ratings, Music acquisition, Plex account, and About & updates. Phones open a page per category; larger displays keep the category list beside the selected page. The mini-player remains available.
Open Settings → Equalizer for ten fixed frequency bands from 31.5 Hz to 16 kHz. Drag a point up to boost that range or down to cut it, up to ±12 dB. All ten points stay together on one graph with a smooth connecting line. Each band adjusts independently; tap a band and use minus/plus for precise changes. Choose Flat, Bass lift, Warm, Vocal, Bright or Lively as a starting preset. Preamp controls overall EQ level without automatic volume reductions. Reset to flat centers all bands and preamp; switching EQ off keeps the settings. TV remote left/right selects a control and up/down adjusts the selected band.
Settings save on this device and apply to local or received playback. The earlier curve-editor preview starts flat/off on upgrade. See implementation and validation.
Use Rooms to join or host a room, share guest/display QR codes, or transfer and take back playback. The Settings hub also links to Rooms.
For browser guests, choose Invite guests. Type the short local address shown
on the host (for example, http://192.168.1.20:8788) and enter the room's four-letter
code. Both devices need the same Wi-Fi. No long invitation URL is required; QR
scanning and shared links remain optional. An old browser tab asks for the current
room code when its previous access expires.
For a screen without a camera, choose Open room display on the host. Connect the other device to the same Wi-Fi, type the short local address shown in its browser, and enter the four-digit display code. QR scanning remains optional.
Automatic mix sets the rated/unrated balance and preference for higher ratings. Selection-strength changes apply to new automatic batches.
Avoid recent repeats defaults to 1 week. Available options are Off, 1 day, 3 days, 1 week, 2 weeks, and 30 days.
- Play and skip history: Automatic tracks are excluded using the newer of Plex last-played time and local play/skip history, including tracks already queued when they come up. Skips count even with automatic ratings off.
- Explicit selections: Explicit requests, Track Radio, and Previous remain available.
- No eligible tracks: The mix stops instead of relaxing the repeat-avoidance window.
- Other devices and apps: Skips are only known when Plex records them.
Automatic ratings requires explicit opt-in before its completion, skip, and repeat-play controls can be adjusted.
- Changes are saved to Plex and can replace existing ratings.
- Turning the feature off does not undo past changes.
- Defaults preserve the earlier tuning.
Preferences stay local to each device. During native transfer, the controlling host's preferences apply.
Music tuning and the Settings layout were introduced in v1.1.8.
For the optional connection in Settings → Music acquisition, see the MusicGrabber integration setup guide.
Use Settings → About & updates → Share app for a QR code linking to harmonicast.app. Phones also offer a share-link action. Browser guest pages include Get the Android app; guests can continue using the browser without installing anything.
Use Settings → About & updates → Check for updates to check GitHub Releases. Automatic checks run on each fresh launch by default; an existing opt-out is preserved. Available updates offer Update now or Later, and downloading is always your choice. You can turn automatic checks off in Settings. Harmonicast verifies the APK checksum, package, newer version code and matching signing certificate before opening Android’s installer. If prompted, allow Harmonicast to install apps, then return and tap Install update. Installing restarts the app; same-key updates preserve settings and local data.
If music stops with the screen off, use Settings → Playback → Background playback settings to review Android battery optimization. Uninterrupted playback under every OEM battery policy is not guaranteed. See validation notes.
Use Java 21 and Android SDK 35 through the checked-in wrapper helper:
./android/build-debug.sh
./scripts/release-check.sh
./android/build-release.shSet JAVA_HOME and ANDROID_HOME for another workstation. Do not use Java 25 with this Kotlin toolchain. Signed builds require your own ignored signing.properties and keystore; android/create-release-keystore.sh helps create them. Keep the same signing key for upgrades. Release APKs are written to android/releases/. Releases use vX.Y.Z tags from main.
Harmonicast is not affiliated with Plex. Licensed under AGPL-3.0-or-later.