# Open Stress: HRV Notifier — Stress level insights & alerts

> Stress level insights & alerts (iPhone/iPad app by Sihang Chen.)

- Source: https://appshunter.io/ios/app/open-stress-hrv-notifier/id6792768616 (this page in markdown: same URL + `.md`)
- Developer: [Sihang Chen](https://appshunter.io/developer/1479493730)
- Category: Health & Fitness
- Price: Free with in-app purchases
- Age rating: 12+
- Requires: iOS 17.0 · 5 MB
- Languages: American English
- Released: 2026-08-04
- Data updated: 2026-08-06
- User reviews in markdown: https://appshunter.io/ios/app/open-stress-hrv-notifier/id6792768616/reviews.md

## What is Open Stress?

Open Stress is a privacy-first iPhone wellness app for HRV observations already stored in Apple Health. It turns those sparse readings into on-device views of the latest raw SDNN value, a 28-day personal baseline, a personal HRV level, a separate personal stress estimate, and 7/30/90-day trend summaries.

The app is designed around observations, not continuous monitoring. Today shows raw HRV in milliseconds, not a percentage. Trends reports counts and shares of observations rather than inventing stress duration. Insights explains freshness, context, baseline coverage, and evidence-labeled actions such as slow breathing, regular aerobic activity, sleep support, less evening alcohol, and smoking cessation.

Open Stress reads Apple Health HRV. When iOS delivers a new qualifying observation, optional notifications can provide a local, timestamped update. The app has no account, product server, ads, or third-party analytics. Data are completely local on your iPhone. There is no account, sign-in, backend servers. As all apps should be.

An auto-renewable annual subscription unlocks full access. Eligible new subscribers receive a 7-day free trial; Apple determines eligibility. There is no charge during the trial. After the trial, the U.S. price is $9.99 per year, and the App Store shows your localized price before purchase. Unless canceled at least 24 hours before the trial or current subscription period ends, the subscription renews automatically each year. You can manage or cancel it in App Store account settings.

Privacy Policy: https://kiskir.dev/projects/open-stress/privacy

Terms of Use: https://kiskir.dev/projects/open-stress/terms

Disclaimer: Open Stress provides personal wellness estimates, not medical diagnoses. HRV can change for many reasons, and one observation is not the whole picture.

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| Open Stress Annual | $9.99 | per year |



## Version history (last 1 release)

### 1.0 — 2026-08-04

No release notes.

## More apps by Sihang Chen

- [Meditating Dot](https://appshunter.io/ios/app/meditating-dot/id1479493731)
- [Twenty2020](https://appshunter.io/ios/app/twenty2020/id1506361681)
- [LoopCam: AR workout counter](https://appshunter.io/ios/app/loopcam-ar-workout-counter/id6772089467)
- [Archi's Torch 3D Scanner](https://appshunter.io/ios/app/archis-torch-3d-scanner/id6775317018)
- [Steps — Simple Pedometer](https://appshunter.io/ios/app/steps-simple-pedometer/id6791997010)

All apps by Sihang Chen: https://appshunter.io/developer/1479493730

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-06.*