letter maps

Guides

Offline & on-device recognition

Privacy on a teleprompter comes down to one question: where do your script and your voice actually go? With letter maps, the answer is your own device.

Where your script lives

  • Scripts and settings are saved in your browser's localStorage only.
  • Nothing is sent to or stored on a server — there's no account and no database.
  • Clearing your browser's site data deletes them; switching devices won't carry them over.

Where your voice is processed

  • In auto-scroll mode, no microphone is used at all.
  • In standard voice mode, microphone audio is sent to your browser's speech service (e.g. Google) for transcription.
  • On Chrome 139+ with on-device recognition enabled, speech runs locally and microphone audio never leaves your machine.

Using on-device recognition

Turn it on in settings on a supported browser. The first time you use a language, Chrome downloads a model once; after that, voice-following works locally — even offline — with audio kept on the device. It's the most private way to use voice mode.

Keep it on your device

Frequently asked questions

Does my script get uploaded anywhere?
No. Your script stays in your browser's localStorage — there's no server copy and no account.
Is my microphone audio sent to the cloud?
In standard voice mode it's sent to your browser's speech service for transcription. With on-device recognition on Chrome 139+, audio stays on your machine.
Can I use voice-following completely offline?
Yes, on Chrome 139+ with on-device recognition enabled and the language model already downloaded.

Related: Browser support, Features, Pricing