# OpenRadiation vs Diffraction Grating Calculator

The clearest difference is price: OpenRadiation at Free against Diffraction Grating Calculator's $2.99. OpenRadiation also leads on update cadence (every 3 months vs every 29 months). Diffraction Grating Calculator's advantage is iOS requirement (13 vs 15.0). On ads, in-app purchases and device support there is nothing between them.

OpenRadiation is free to download; Diffraction Grating Calculator costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

OpenRadiation ships an update every 3 months, Diffraction Grating Calculator every 29 months. The most recent releases landed on October 7, 2026 and September 29, 2026 respectively.

## The numbers

| Metric | OpenRadiation | Diffraction Grating Calculator |
| --- | --- | --- |
| Price | **Free** | $2.99 |
| Rating | **[2.0 (4 ratings)](https://appshunter.io/ios/app/openradiation/id1246249831/reviews)** | — |
| Number of ratings | **4** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 29 months |
| Monetization | Free | — |
| Size | 57 MB | 1 MB |
| Requires iOS | 15.0 | **13** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [ASNR](https://appshunter.io/developer/1861431469) | [Nitrio](https://appshunter.io/developer/321121189) |

## What reviewers say

### OpenRadiation

[App page](https://appshunter.io/ios/app/openradiation/id1246249831)

Measure ambient radioactivity levels and assess your exposure to ionizing radiation using a compatible sensor. Contribute to a citizen science project by sharing your measurements to build a collaborative database.

**Highlights:** Measure radioactivity levels, Assess radiation exposure, Contribute to citizen science, Collaborative data database, Share measurements, View data online

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

**In-app purchases:** none


### Diffraction Grating Calculator

[App page](https://appshunter.io/ios/app/diffraction-grating-calculator/id1413088894)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is OpenRadiation free?

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

### Is Diffraction Grating Calculator free?

Diffraction Grating Calculator costs $2.99, with no in-app purchases.

### Do OpenRadiation or Diffraction Grating Calculator have ads?

Neither OpenRadiation nor Diffraction Grating Calculator shows ads.

### Which is updated more often, OpenRadiation or Diffraction Grating Calculator?

OpenRadiation ships an update every 3 months, and Diffraction Grating Calculator every 29 months. Most recently, OpenRadiation was updated on October 7, 2026 and Diffraction Grating Calculator on September 29, 2026.

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