Privacy Policy for Breathing Trainer

Last updated: July 12, 2026

Breathing Trainer is a guided breathing app that helps you calm your nervous system and shows, through your heart‑rate variability (HRV), how each session settles you down. It is built to be private by design: there is no account, no advertising, and no cross‑app tracking. Your breathing sessions and heart‑rate history are processed and stored on your device. This policy explains exactly what data the app uses, where it goes, and how you stay in control.

Short version: No account. No ads. No cross‑app tracking. Your pulse and HRV are measured on your device — with Apple Health or your finger on the camera — and camera frames are never saved or uploaded. Your session history stays on your device. We use Firebase for anonymous usage analytics and crash reports, and Apple/RevenueCat for subscriptions. You can delete all of your on‑device data at any time.

1. Heart Rate & HRV via Apple Health (HealthKit)

To show how a breathing session affects your body, the app can read your heart‑rate variability (HRV / SDNN) and heart rate from Apple Health, and can write completed sessions back to Apple Health as Mindful Minutes. This is optional and only happens after you grant HealthKit permission.

What is used: heart‑rate and HRV samples you have in Apple Health (for example, from your Apple Watch) before and after a session, to compute your calm/HRV change.
Where it goes: health data is read and processed on your device and stored in Apple Health and in the app's local database. It is never transmitted to us or any third party, and is not used for advertising.
Your control: you can grant or revoke Health access at any time in the iOS Settings → Health → Data Access & Devices → Breathing Trainer. Health data is never shared through analytics or crash reporting.

2. Camera Pulse Measurement (on device only)

If you do not have an Apple Watch, the app can estimate your pulse by having you rest a fingertip over the rear camera and flash (a technique called photoplethysmography, or PPG). This feature is optional — you can skip the reading and still use the app.

What is collected: while measuring, the app reads the brightness of live camera frames in memory to detect your pulse. It does not record video or take photos.
Sharing / third parties: none. Camera frames are processed live on your device and are never saved, photographed, or uploaded. Only the resulting numeric pulse / HRV estimate is stored locally.
Retention: camera frames are held only transiently in memory during the reading and discarded immediately after each frame is processed.
Your control: the camera permission is requested only when you start a reading, and you can decline or skip it.

3. Notifications

If you allow notifications, the app schedules local reminders (for example, a daily nudge to breathe) on your device. These are local notifications and are not sent through any external server.

4. Analytics & Crash Reports

To understand how features are used and to fix crashes, Breathing Trainer uses Google's Firebase Analytics and Crashlytics. This collects anonymous, aggregated product events (for example, which screen was opened or that a breathing session was started or completed) and crash diagnostics, together with a device identifier and basic device data. This data is not linked to your identity (there is no account), is used only to improve the app, and is not used to track you across other companies' apps or websites. Your health data, HRV values, and camera data are never included in analytics. We do not use advertising SDKs and do not sell your data.

5. Subscriptions & Purchases

Breathing Trainer Pro is sold as an auto‑renewing subscription or a one‑time lifetime purchase. Purchases are processed by Apple. We use RevenueCat to validate and restore purchases; RevenueCat receives a randomly generated app user identifier and your purchase/transaction status (not your name or email). See Apple's and RevenueCat's privacy policies for details.

6. Data We Collect — Summary

Identity / contact data: none. No account or sign‑in.
Health data: heart rate and HRV read from Apple Health, and Mindful Minutes written back, only with your permission; processed on device and never transmitted to us (see Section 1).
Camera data: transient camera brightness used only to estimate your pulse; never stored as images and never uploaded (see Section 2).
Usage analytics & crash reports: anonymous product and crash data via Firebase (Google), not linked to your identity and not used for cross‑app tracking (see Section 4).
On‑device content: your breathing sessions, HRV history, streaks and settings are stored only on your device.
Purchase status: handled by Apple / RevenueCat as described above.

7. Third Parties We Share Data With

We share only the limited data described above, and only with the following processors, each of which is required to provide the same or equal protection of your data:

Google Firebase — anonymous analytics and crash reporting.
RevenueCat and Apple — subscription processing.

8. How Long We Keep Data & Deleting It

On‑device data stays until you remove it. Open Settings → Delete all my data in the app to erase your sessions and HRV history, or delete the app to remove all locally stored content. To stop writing sessions to Apple Health, turn off Health access in iOS Settings. Health data you choose to keep in Apple Health is managed by you in the Health app.

9. Children

Breathing Trainer is not directed to children under 13 and does not knowingly collect data from them.

10. Wellness Disclaimer

Breathing Trainer is a wellness and relaxation app — it is not a medical device and does not diagnose, treat, or cure any condition. Heart‑rate, HRV, and calm estimates are for wellness and habit‑building only and are approximate. For any health concern, consult a qualified professional.

11. Changes to This Policy

We may update this policy as the app evolves. Material changes will be reflected by the "Last updated" date above.

12. Contact

Questions about privacy? Email [email protected].