R Rhydhm Privacy Policy

Privacy

Sleep data stays close.

Rhydhm is built as a local-first sleep experiment. It uses the phone speaker, microphone, motion sensors, and alarm permissions to estimate room surfaces, movement, and breathing signals.

Last updated: May 11, 2026 Applies to Rhydhm Android builds

Sensors

Audio and motion are used for sleep tracking.

The app may play quiet or ultrasonic tones through the speaker and use the microphone to read echoes from the room. It may also use accelerometer and motion data to detect whether the phone moved during a session.

Session data

Sessions are stored on the device by default.

Sleep sessions can include time series summaries, surface detections, movement estimates, microphone loudness, phone motion readings, alarm events, and app diagnostic state. Raw microphone audio is not intended to be stored by default.

Diagnostics

Developer telemetry is opt-in lab data.

Some test builds include developer diagnostics for sending batches to a local computer or local network endpoint. That mode is for debugging signal quality and should be used only when you intentionally enable it.

Analytics

High-level analytics may be used in beta builds.

Beta builds may send high-level product events through PostHog, using event names prefixed with SleepTracking. These events are intended to help understand crashes, feature use, and setup success. They are not intended to include raw audio, exported session files, or sleep diary content.

Export

You control exported files.

If you export a session, the exported file is created so you can inspect, compare, or share it. Anyone you send that file to may be able to see the sleep session metrics and diagnostics inside it.

Deletion

Delete local sessions from the app or device storage.

Rhydhm does not rely on a central Rhydhm cloud for normal session storage. Deleting a local session or app storage removes the data under your control on that device.

Details

What Rhydhm collects and why

Rhydhm is a wellness and research app, not a medical device. Sensor data is used to estimate whether acoustic sleep tracking is working in your room and to support alarm timing experiments.

Data used by the app

  • Microphone input for echo, loudness, and signal quality analysis.
  • Speaker output settings for test tones, chirps, sweeps, and alarm sounds.
  • Accelerometer or device motion readings to detect phone movement.
  • Notification and alarm settings, including alarm time, wake window, snooze, sound, and dismissal mode.
  • Session summaries such as detected surfaces, movement estimates, candidate body ranges, and breathing estimates when available.

Why it is used

  • Establish a room baseline and detect stable echo surfaces.
  • Estimate motion near a candidate body surface during sleep.
  • Estimate breathing rate when the signal is strong enough.
  • Run alarms, snooze, and wake-opportunity experiments.
  • Debug why a device or room setup cannot produce a reliable signal.

Sharing

  • We do not sell sleep data, audio data, sensor data, or alarm data.
  • We do not use sleep data for advertising.
  • Exports and diagnostic uploads happen only when a feature or test workflow causes them.
  • High-level beta analytics may be sent to PostHog, but raw audio and exported session files should not be sent as analytics events.

Security and retention

  • Normal session data is stored on the device unless you export it or enable a diagnostic transfer.
  • Diagnostic files sent to your own computer are stored wherever that local receiver writes them.
  • Uninstalling the app or clearing app storage may delete local session history.
  • Because the product is still experimental, keep separate backups of any data you need to preserve.

Health disclaimer

Rhydhm is not intended to diagnose, treat, prevent, or monitor a disease or medical condition. Sleep stage, breathing, and movement estimates can be wrong, especially during beta testing.