Privacy Policy

Last Updated: July 4, 2025

Your privacy is critically important to us. This policy outlines how Sanctuary: Sleep Monitor ("the app") handles your data.

Core Principle: Your Data Stays on Your Device

We designed this app with a "privacy-first" approach. All sensor data processing and analysis happens exclusively on your device. We do not have servers, and we do not collect, store, or transmit your personal or sensor data.

What Information We Use & Why

• Microphone Access: Used solely to measure ambient sound (decibel) levels. The audio is processed in real-time and is never recorded or saved.
• Sensor Access (Accelerometer, Gyroscope, Magnetometer, etc.): Used to measure vibration, light, temperature, humidity, and EMF levels. This data is processed locally and discarded.
• Location Access: Used one-time (per request) to fetch local sunrise and sunset times from a public. Your precise location is not stored or shared by our app.
• Write Settings Permission: Required for the "Sunrise Alarm" feature to gently increase your screen's brightness. The app only changes brightness during the alarm and restores the original setting afterward.

Data Storage

The app uses your device's local storage (Preferences) to save your settings, such as thresholds, theme choice, and chronotype. This information is never transmitted off your device.

Background Services

We use the foreground servicei API in android to track varous sensors. Foreground service included are FOREGROUND_SERVICE_TYPE_DATA_SYNC.

Third-Party Services

We use the public, anonymous `api.sunrise-sunset.org` API for circadian data. We send only your device's latitude and longitude; no personal identifying information is included in this request.

Changes to This Policy

We may update this privacy policy from time to time. We will notify you of any changes by posting the new policy on this page.