# HemiPhysioData vs OpenPPG

The clearest difference is update cadence: OpenPPG at monthly against HemiPhysioData's every 18 months. HemiPhysioData's advantage is device support (3 vs 1) and iOS requirement (13.2 vs 17.6). On price, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

HemiPhysioData ships an update every 18 months, OpenPPG monthly. The most recent releases landed on June 4, 2026 and September 24, 2026 respectively.

## The numbers

| Metric | HemiPhysioData | OpenPPG |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 18 months | **Monthly** |
| Monetization | Free | — |
| Size | 2 MB | 9 MB |
| Requires iOS | **13.2** | 17.6 |
| Devices | **iPhone, iPod, Apple Watch** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Moez ur Rehman](https://appshunter.io/developer/1502416676) | [research app](https://appshunter.io/developer/1807596075) |

## What reviewers say

### HemiPhysioData

[App page](https://appshunter.io/ios/app/hemiphysiodata/id1502983547)

This app collects raw and processed sensor data from your Apple Watch, including accelerometer and gyroscope readings. It allows you to select activities, preferences, and then exports the data as a CSV file to your iPhone for analysis. Ideal for tracking movement and Range of Motion (ROM) measurements.

**Highlights:** Collects raw and processed sensor data, User-friendly activity selection, Exports data as CSV files, Supports accelerometer and gyroscope, Configurable sampling rate, Haptic feedback for logging alerts

**In-app purchases:** none


### OpenPPG

[App page](https://appshunter.io/ios/app/openppg/id6744415040)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is HemiPhysioData free?

HemiPhysioData is free to download, with no in-app purchases.

### Is OpenPPG free?

OpenPPG is free to download, with no in-app purchases.

### Do HemiPhysioData or OpenPPG have ads?

Neither HemiPhysioData nor OpenPPG shows ads.

### Which is updated more often, HemiPhysioData or OpenPPG?

HemiPhysioData ships an update every 18 months, and OpenPPG monthly. Most recently, HemiPhysioData was updated on June 4, 2026 and OpenPPG on September 24, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*