Privacy

Last updated: August 2026

Summary

Number Trainer works without an account — progress can stay on your device only. If you choose to sign in, we store your profile and learning progress in our database so you can sync across devices. Speech is generated by contacting our server and Microsoft’s TTS service.

Stored on your device

• Progress — levels unlocked, numbers heard, practice stats, and preferences in browser localStorage (always, even when signed in).
• Sign-in session — Auth0 tokens in browser storage when you use Account sign-in (localStorage by default).
• Audio cache — generated speech clips in IndexedDB. Clear via site data / app storage in browser or device settings.
• Mobile config — Capacitor builds may ship a config.json with the API URL (apiBase).

Accounts (optional sign-in)

Sign-in is provided by Auth0 using social providers (Google, Apple, Microsoft, Facebook). We receive your Auth0 user id and, when available, your name, email, and profile picture from the provider.

When signed in and the server database is enabled, we store in Azure Cosmos DB:

• Profile (users) — user id, email, name, picture, sign-in provider, login count, last login time, last IP address and browser user-agent from sign-in requests.
• Progress (user-progress) — learn/practice progress and app settings synced from your device.
• Activity log (user-events) — sign-in, sign-out, and progress sync events (timestamp, event type, basic metadata).
• Feedback — if you submit feedback while signed in, your user id and email may be attached to the report.

You can export your cloud progress from the Account page when signed in, or delete your cloud profile, progress, activity log, and linked feedback from there. Deleting cloud data does not remove your Auth0 account with the social provider — only data stored by Number Trainer.

Sent to the app server (all users)

When you hear a number, the client requests audio from the API. Requests may include:

• The number, practice language, and speech speed.
• Standard HTTP data: IP address, user agent, timestamps.

TTS clips may be cached in Cosmos DB after first synthesis (shared cache, not tied to your account). Server logs depend on your host (e.g. Azure App Service).

Text-to-speech provider

Speech uses Microsoft Edge online TTS (edge-tts-universal). Number text and language are sent to Microsoft to produce audio. See Microsoft’s privacy practices. This integration is unofficial and may change without notice.

Fonts

The UI loads fonts from Google Fonts. Google may receive your IP address when fonts are fetched. See Google’s privacy policy.

Retention

• Cloud account data is kept until you delete it from Account or ask us to remove it.
• Device data remains until you clear site/app storage.
• TTS cache entries are shared and not user-specific.

Children

The app does not knowingly collect personal information from children under 13. Sign-in is optional and uses third-party providers subject to their own policies.

Your choices

• Use the app without signing in (device-only progress).
• Export or delete cloud data from Account when signed in.
• Clear local progress by removing site data / app storage.
• Stop using the app at any time.

Contact

Privacy questions: Tech4utexas@gmail.com or the in-app feedback form.