Synced lyrics on Rokid AR glasses, streamed live from your phone over Bluetooth.

Phone companion app · Rokid Glasses live display

Spotify's own synced lyrics are now a first-class provider on the phone, ported from the iOS companion app.

• Added a SPOTIFY provider at the top of the chain: Spotify -> Musixmatch -> Netease -> LRCLIB
• When Spotify is the active player, the app reads the exact track ID from its media session, so Spotify lyrics need no search heuristics at all
• Added an in-app Spotify login that captures the sp_dc cookie automatically, plus a manual paste field as fallback; the cookie stays on the device in encrypted storage
• Without the cookie, or for non-Spotify players, the existing chain works exactly as before

Previous chantier: turning the phone app into a real multi-provider lyrics pipeline instead of a single-source prototype (Musixmatch sign-in, lookup dedup, graceful fallback messaging).

The phone app watches the active Android media session, detects the current track, fetches synced lyrics from a provider chain, and streams the result to the glasses over Bluetooth Classic SPP.

Current provider order:

1. Spotify color-lyrics when Spotify is playing and an sp_dc cookie is configured
2. Musixmatch as the main authenticated provider
3. Netease as the secondary fallback
4. LRCLIB as the public final fallback

When the glasses connect, they receive a full lyrics snapshot first, then lightweight progress sync events as the song plays so the HUD stays in sync in real time.

No internet is required on the glasses side. No cloud relay. Everything runs locally between the phone and the glasses.

• Time-synced lyrics on Rokid AR glasses for the currently playing track
• Multi-provider lookup pipeline with graceful fallback
• Works with Android media sessions instead of being tied to one specific player
• Runs entirely over Bluetooth between the phone and the glasses
• Press Enter on the glasses to play or pause music on the phone

android-phone/       Android phone runtime (media monitor + BT server + lyrics engine)
android-glasses/     Android glasses client (BT client + HUD renderer)
shared-contracts/    Shared Bluetooth wire protocol and lyrics data contracts
design/              UI mockups and design references

# Phone APK
android-phone/gradlew.bat assembleDebug

# Glasses APK
android-glasses/gradlew.bat assembleDebug

Release builds read signing values from environment variables or matching Gradle properties:

• ANDROID_KEYSTORE_PATH
• ANDROID_KEYSTORE_PASSWORD
• ANDROID_KEY_ALIAS
• ANDROID_KEY_PASSWORD
• ROKID_LYRICS_VERSION_NAME (optional)
• ROKID_LYRICS_VERSION_CODE (optional)

assembleRelease falls back to the debug keystore if those values are absent so you can validate the release path locally or in CI. GitHub Actions uses the real release keystore when all signing secrets are configured, otherwise it falls back to the debug keystore and still publishes release APK artifacts. Partial signing configuration fails the build.

The Spotify provider fetches Spotify's official line-synced lyrics for the exact track playing in the Spotify app. It needs your own sp_dc session cookie, and there are two ways to provide it:

In-app login (easiest). Tap [ SET UP SPOTIFY ] -> [ LOG IN WITH SPOTIFY ] and sign in on the Spotify page that opens. The app reads the sp_dc cookie from its own WebView the moment the login completes, saves it, and wipes the WebView session — nothing else is kept. The login always starts from a clean session, so a leftover cookie from an old visit can never be captured by mistake.

Manual paste (fallback). Grab the cookie from a logged-in Spotify web session on a desktop browser:

1. Open https://open.spotify.com/ and log in with your own account
2. Open DevTools and go to Application -> Storage -> Cookies -> https://open.spotify.com
3. Copy the Value of the sp_dc cookie
4. Paste it into the same dialog — the raw value, sp_dc=value, or a full Cookie: header all work

Either way the cookie is stored in encrypted preferences on the phone and never leaves the device. If lookups start reporting an anonymous token, the cookie is stale: log in again from the app, or paste a fresh value.

Keep in mind sp_dc is an account session cookie, not an API token — treat it like a password, never share or commit it. Spotify's color-lyrics endpoint is an internal API that can change without notice, so this provider is best-effort by design; the rest of the chain covers the gaps.

1. Install lyrics-phone-debug.apk on the Android phone and lyrics-glasses-debug.apk on the Rokid device
2. Pair the phone and the glasses over Bluetooth at the OS level first
3. Open the phone app and grant Bluetooth and notification permissions
4. Tap [ NOTIF ACCESS ] and enable the notification listener for Rokid Lyrics
5. Optional but recommended: sign in to Musixmatch, and paste your Spotify sp_dc cookie if you use Spotify (see above)
6. Start playing music on the phone
7. Open the glasses app and wait for the status to show CONNECTED
8. Lyrics should appear on the glasses display within a few seconds
9. Press Enter on the glasses to play or pause playback on the phone