WatchHAR Privacy Policy

Last Updated: December 11, 2025

        Summary: WatchHAR does not collect, store, or transmit any personal data. All processing happens locally on your Apple Watch.
    

About WatchHAR

WatchHAR is a research demonstration app developed by the SPICE Lab at Northwestern University for academic purposes. The app demonstrates privacy-preserving human activity recognition technology presented at ACM ICMI 2025.

Data Collection

We do not collect any data.

No personal information is collected
No usage data is collected
No analytics or tracking
No account creation or sign-in required

Sensor Usage

WatchHAR uses the following sensors on your Apple Watch:

Microphone: Used only for on-device activity recognition. Audio data is processed in real-time on your watch and immediately discarded.
Motion Sensors (Accelerometer, Gyroscope): Used for detecting physical activities. All processing happens locally on your device.

Data Processing

All sensor data processing occurs entirely on your Apple Watch. The app uses machine learning models that run locally on your device. No data is ever:

Sent to any server
Stored on your device
Shared with third parties
Used for any purpose other than real-time activity recognition

Privacy by Design

WatchHAR is designed with privacy as a core principle. The app demonstrates that effective activity recognition can be achieved without compromising user privacy through on-device processing.

Research Purpose

This app serves as a demonstration of research conducted at Northwestern University's SPICE Lab. It is provided free of charge for academic and educational purposes.

Third-Party Services

WatchHAR does not integrate with any third-party services, analytics platforms, or advertising networks.

Children's Privacy

WatchHAR does not knowingly collect any information from anyone, including children under 13.

Changes to This Policy

We may update this privacy policy from time to time. Any changes will be reflected by updating the "Last Updated" date at the top of this policy.

Contact Us

For questions about this privacy policy or WatchHAR, please contact:

SPICE Lab, Northwestern University
Email: nu.spicelab@gmail.com