Zero Knowledge

Privacy Policy

Your data belongs to you. LingoBudi has no backend, no database, and no access to your content.

Zero-Knowledge Architecture

LingoBudi is a fully client-side application hosted as static files on Cloudflare Pages. There is no backend server, no database, and no analytics that track your conversations. All processing happens directly in your browser using your own API key.

Where Your Data Lives

Your data is stored in exactly two places:

Browser localStorage — Your sessions, vocabulary, language preferences, and API key are stored locally in your browser. This data never leaves your device unless synced to Drive.
Google Drive AppDataFolder — A hidden, app-specific folder in your personal Google Drive that only LingoBudi can read and write. Your primary Drive files are never accessed.

Google OAuth & Permissions

When you sign in, LingoBudi requests the following Google OAuth scope:

drive.appdata — See, create, and delete its own configuration data in your Google Drive

This is the most restrictive Drive scope available. It only grants access to a hidden app-specific folder. LingoBudi cannot read, modify, or delete any of your personal Google Drive files, folders, or documents.

API Key Handling

Your Gemini API key is stored exclusively in your browser's localStorage. It is sent directly from your browser to Google's Gemini API — LingoBudi never sees, transmits, or stores your key on any server. The key is used solely to power AI chat responses and text-to-speech within your browser session.

Deleting Your Data

You have full control over your data at all times:

Wipe Local Cache — In Settings, click "Wipe Local Cache" to permanently delete all sessions, vocabulary, and your API key from this browser.
Revoke Google Access — To remove cloud-synced data, visit your Google Account > Security > Third-party apps and revoke LingoBudi's access. This deletes the AppDataFolder content.
Delete API Key — Visit Google AI Studio and delete the key. This immediately disables all API access.