# Radioactive Decay Simulator vs Rad Onc Calc

The clearest difference is rating: Rad Onc Calc at 4.6 against Radioactive Decay Simulator's 4.0. Rad Onc Calc also leads on update cadence (every 6 weeks vs every 17 months) and ratings volume (12 vs 1). Radioactive Decay Simulator's advantage is iOS requirement (9.3 vs 14.0). On price, ads, in-app purchases and monetization model there is nothing between them.

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

Rad Onc Calc holds the better App Store score, 4.6 against 4.0. That said, the two scores are not equally well evidenced: Rad Onc Calc has 12 ratings behind it against 1, so its average is the more settled of the two.

Radioactive Decay Simulator ships an update every 17 months, Rad Onc Calc every 6 weeks. The most recent releases landed on June 5, 2026 and June 1, 2026 respectively.

## The numbers

| Metric | Radioactive Decay Simulator | Rad Onc Calc |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.0 (1 ratings)](https://appshunter.io/ios/app/radioactive-decay-simulator/id959357000/reviews) | **[4.6 (12 ratings)](https://appshunter.io/ios/app/rad-onc-calc/id1494077153/reviews)** |
| Number of ratings | 1 | **12** |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 17 months | **Every 6 weeks** |
| Monetization | Free | Free |
| Size | 20 MB | 57 MB |
| Requires iOS | **9.3** | 14.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 12+ |
| Developer | [Alistair Shaw](https://appshunter.io/developer/959356999) | [Red Canvas LLC](https://appshunter.io/developer/1435398886) |

## What reviewers say

### Radioactive Decay Simulator

[App page](https://appshunter.io/ios/app/radioactive-decay-simulator/id959357000)

This educational tool simulates radioactive decay for a group of atoms. Users can choose preset atoms or input custom half-lives to observe decay in real-time graphs. The simulator allows for adjustments in atom count and speed for efficient analysis.

**Highlights:** Emulates radioactive decay, Select preset or custom atoms, Adjust atom count, Real-time decay graphs, Adjustable simulation speed

**Features:** macOS Compatibility

**In-app purchases:** none


### Rad Onc Calc

[App page](https://appshunter.io/ios/app/rad-onc-calc/id1494077153)

A radiation oncology calculator and reference tool for medical professionals. It provides quick access to essential calculations and treatment constraints.

**Highlights:** Radiation oncology calculations, Treatment constraints reference, Quick access to essential data, Comprehensive tool for professionals

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Radioactive Decay Simulator free?

Radioactive Decay Simulator is free to download, with no in-app purchases.

### Is Rad Onc Calc free?

Rad Onc Calc is free to download, with no in-app purchases.

### Which has better reviews, Radioactive Decay Simulator or Rad Onc Calc?

Rad Onc Calc is rated higher. Radioactive Decay Simulator averages 4.0 out of 5 from 1 ratings, while Rad Onc Calc averages 4.6 from 12 ratings.

### Do Radioactive Decay Simulator or Rad Onc Calc have ads?

Neither Radioactive Decay Simulator nor Rad Onc Calc shows ads.

### Which is updated more often, Radioactive Decay Simulator or Rad Onc Calc?

Radioactive Decay Simulator ships an update every 17 months, and Rad Onc Calc every 6 weeks. Most recently, Radioactive Decay Simulator was updated on June 5, 2026 and Rad Onc Calc on June 1, 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.*