Privacy Policy

Crane is privacy-first. All posture detection happens 100% on your device. No camera data ever leaves your computer.

What Crane Does

Crane uses your device's webcam and on-device AI (TensorFlow.js with MoveNet) to detect your posture in real time. All posture processing happens locally on your computer.

Data We Collect

Crane collects the absolute minimum needed to operate:

• Camera feed — Processed in real time by the local AI model. Never recorded, stored, or transmitted.
• Posture data — Calculated locally and displayed to you. Posture session statistics (scores, timestamps) are saved locally on your device for your own review. Never sent to any server.
• Settings and preferences — Saved locally on your device in a settings file. Never sent anywhere.
• License keys — Stored locally on your device. Validated cryptographically on-device (Ed25519 signature verification).
• Device identifier — A one-way hash of your machine ID, used solely to register your device when activating a Pro license. This hash cannot be reversed to identify your machine or you personally.

Network Activity

Crane operates almost entirely offline. The only network requests Crane makes are:

• License activation — When you activate a Pro license key, Crane sends the key and a hashed device identifier to our license server (hosted on Supabase) to register the device. This happens once per device.
• Heartbeat — On each app launch, Pro users send a lightweight ping to update the "last seen" timestamp for their device. This contains only the hashed device ID and timestamp — no personal data, posture data, or usage analytics.

There are no analytics, telemetry, crash reporting, advertising, or tracking of any kind. Free-tier users make zero network requests. App updates are handled by the Microsoft Store.

Third-Party Services

Crane uses Supabase (a hosted PostgreSQL service) solely for Pro license device registration. No personal data, posture data, or usage data is stored on this service — only hashed device IDs, license keys, and activation timestamps. Crane does not integrate with any analytics platforms, advertising networks, or data brokers.

Camera Access

Crane requests camera access solely for real-time posture detection. The camera feed is:

• Processed frame-by-frame by the on-device TensorFlow.js model
• Never recorded to disk
• Never transmitted over any network
• Discarded immediately after each frame is analyzed

You can revoke camera access at any time through your operating system's privacy settings.

Children's Privacy

Crane does not collect any data from any user, including children. The app is suitable for all ages.

Changes to This Policy

If we ever change this policy (for example, by adding optional cloud features), we will update this page and the date above. Any significant changes will be communicated through the app's update notes.

Contact

For questions about this privacy policy, contact us at: team@crane.blue