policies

Privacy Policy — Rythm

Last updated: July 5, 2026

Summary

Rythm stores all your data on your device. We do not collect, transmit, or share your personal information.

Data We Store

Rythm has no account or sign-in of any kind. All data is stored locally on your device using Apple’s SwiftData framework:

• Daily recovery, sleep, strain, and stress scores computed from Apple Health data
• Personal baselines (HRV, resting heart rate, sleep duration) calculated from your own history
• Profile details you provide (name, birth date, biological sex, body weight, sleep goal)
• Your reminder preference (whether the morning reminder is on, and its time)
• Subscription status (cached locally, verified against Apple’s records)

Apple Health (HealthKit)

Rythm requests read-only access to Apple Health. It never writes any data back to Apple Health. Rythm reads the following, entirely on-device:

• Heart rate, heart rate variability (HRV), and resting heart rate
• Blood oxygen (SpO2)
• Sleep analysis
• Respiratory rate
• Active and resting (basal) energy burned
• Step count
• Body weight
• Cardio fitness (VO₂ max)
• Workouts (used to estimate your personal max heart rate)
• Date of birth and biological sex (used to personalize score calculations)

All of this data is processed on your device to compute your recovery, sleep, strain, and stress scores, and your Cardio Fitness Age estimate. None of it is uploaded, transmitted, or shared with us or anyone else.

You can manage HealthKit permissions at any time in iPhone Settings → Privacy & Security → Health → Rythm.

AI Insights

Rythm’s daily insights are generated on-device using Apple’s on-device Foundation Models (Apple Intelligence). Your health data never leaves your device to generate these insights — there is no server-side AI processing.

Notifications

If you enable the optional morning reminder, Rythm schedules a local notification on your device at the time you choose. It is a simple, generic reminder — it contains no health data or personal scores — and is scheduled entirely on-device with no server involved. You can turn it off any time in Rythm’s Profile settings, or in iPhone Settings → Notifications → Rythm.

Data We Do Not Collect

• We do not use analytics or crash reporting tools
• We do not track your location
• We do not share any data with third parties
• We do not have servers or a backend — there is no user account beyond what’s stored on your device

Subscriptions

Subscription purchases and management are handled entirely by Apple. We receive only a verified transaction confirmation — we never see your payment information. See Apple’s Privacy Policy at https://www.apple.com/legal/privacy for details on how Apple handles payment data.

Children’s Privacy

This app is not directed at children under 13. We do not knowingly collect data from children.

Changes to This Policy

We may update this policy. Continued use of the app after changes constitutes acceptance. The “Last updated” date above will reflect any changes.

Contact

Questions? Email us at: app [at] bramhand [dot] com