Offline Audio Player

Auto-paired transcripts · airplane-mode ready
No folder selected. Tap "Pick folder" and select your audio folder.
How this works / tips
• Tap Pick folder and select the folder containing your audio + transcript files.
• Audio (mp3, m4a, wav, ogg, opus, flac, aac, webm) and matching .txt/.md transcripts (same base name) auto-pair.
Timestamp sync: if transcript lines start with timestamps like [00:01:23], the transcript scrolls line-by-line. Tap a timestamp to jump.
True background playback (screen off): works for any audio file. For text-only transcripts, run the included prerender.py on your PC to generate a paired MP3 — then it plays in background like any other audio.
Read aloud (in-browser TTS) uses the browser speech engine; fine while the screen is on, but most mobile browsers pause it when backgrounded. Pre-render is the workaround.
Samsung phones — required settings
One UI's battery management overrides Chrome's "Unrestricted" setting and will pause background audio. Disable it manually:

1. Settings → Battery and device care → Battery → Background usage limits
   Make sure Chrome is NOT in the Sleeping apps or Deep sleeping apps lists. If it is, tap the entry and remove it.

2. Settings → Apps → Chrome → Battery
   Set to Unrestricted.

3. Settings → Battery and device care → Battery → More battery settings
   Turn OFF Adaptive battery (or at least exempt Chrome).

4. Settings → Battery and device care → Auto-optimization (if present)
   Turn OFF — the daily 3 AM "optimize" can re-add Chrome to sleeping apps.

If audio still cuts on background after these are set, expand the Diagnostic log below right after a cut-out and copy the contents — the events around the cut-out tell us whether the OS killed the page (no events at the cut-out) or paused the audio element via Media Session (a pause event appears).
v
2 Track no tracks
Nothing playing
TTS voice & pacing
0.95×
1.00
280ms
For true background TTS (screen off): on your PC, run python prerender.py in your audio folder. It uses Microsoft Edge's neural TTS (free, no API key, US English voices) to produce an MP3 alongside each transcript. The MP3 plays as a regular audio file with full lockscreen / background support.
Transcript
No transcript loaded.