// PRIVACY

Privacy Policy

Local-first · Zero telemetry · Your data belongs to you

Last updated: 2026-08-09

1. Introduction

YuzhouHe (“we” or “the app”) is a local-first toolbox application. This policy explains how we handle your data. In one sentence: the vast majority of features work fully offline; your data stays only on your device, encrypted — we collect no telemetry and ship no ad or analytics SDKs.

2. Local-first: what we collect

  • We collect no telemetry, crash analytics, or usage behavior data; the website (yuzhouhe.com) uses no cookies and no third-party tracking.
  • Your tool data (notes, todos, encrypted notes, encrypted photos, contacts, password vault, TOTP, clipboard history, AI projects, etc.) is stored only on your device, encrypted at rest with AES-256 via Hive; the master key is derived with Argon2id and protected by the Android hardware Keystore.
  • We operate no cloud accounts, require no registration, and never access your contacts, SMS, or call logs.

3. Encryption and storage (zero-knowledge architecture)

  • All sensitive data is encrypted with AES-256-GCM authenticated encryption; keys exist only on your device (Keystore) — we cannot read your data.
  • Backups are always encrypted (PBKDF2 300k / Argon2id + AES-256-GCM); the backup password is set by you, and unencrypted backups are refused.
  • Changing your master password re-encrypts all encrypted data locally, automatically, never leaving your device.

4. When we go online (always triggered by you)

Network requests only happen when you act:

  • AI chat / AI coding: requests are sent directly to the provider you chose in settings (e.g. DeepSeek, Kimi); if you configured a self-hosted relay, they go through your relay server. Your API keys stay only on your device (Keystore).
  • AI web search: runs when you tap “search online”, using Bing by default.
  • Translation / voice (TTS/ASR): uses the providers configured in settings (e.g. Tencent, Baidu, Volcano Engine).
  • Update check: fetches the version manifest from the official site when you check for updates; APK downloads are verified by SHA-256 before installation.

The app never connects silently in the background.

5. AI features and third-party services

  • AI providers (DeepSeek, Kimi, Qwen, GLM, etc.) are chosen and configured by you; your conversations are sent to the chosen provider to fulfil requests — see that provider’s privacy policy.
  • We recommend “Bring Your Own Key” (BYOK) mode: keys live only on your device and no intermediary is involved; or use a self-hosted relay for full control of the forwarding path.
  • We never train on your data (we simply don’t have it).

6. Permissions

Permission Purpose
Camera Encrypted camera, QR scanning
Microphone Voice assistant recording, decibel meter
Notifications Countdown / todo reminders (exact alarm requires separate system authorization)
Photos / media Import/export images and videos, save to gallery
Install unknown apps App updates only (can be disabled)

All permissions are requested on demand when you first use the feature and can be revoked in system settings anytime.

7. Backup and export

  • Backup files are created by you and stored by you (locally or on your own WebDAV/cloud); backups are always encrypted — keep your backup password safe: if you lose it, the data cannot be recovered.
  • Exported/shared files are your choice; please assess the recipient yourself.

8. Data deletion

  • Uninstalling the app deletes all local data on the device.
  • You can clear per-tool data, clipboard history, and AI projects anytime in the app.
  • Backup files are managed by you; delete them to remove them completely.

9. Children’s privacy

The app is not intended for children under 14, and we do not knowingly collect children’s personal information.

10. Policy updates

  • Updates are published on this site and in the app, with an effective date.
  • Material changes (e.g. new data collection) will be prominently announced in the app.

11. Contact

For privacy questions, contact us via the “Feedback” section on the website or our community channels.

MATRIX MODE: ON — enter again or press ESC to exit