# atom.sim vs Formula Conversion

The clearest difference is in-app purchases: atom.sim at none against Formula Conversion's 1. atom.sim also leads on update cadence (every 7 months vs every 26 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Formula Conversion sells 1 one-off in-app purchase. atom.sim asks for nothing beyond the download.

atom.sim ships an update every 7 months, Formula Conversion every 26 months. The most recent releases landed on October 11, 2026 and September 29, 2026 respectively.

## The numbers

| Metric | atom.sim | Formula Conversion |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 7 months** | Every 26 months |
| Size | 78 MB | 2 MB |
| Requires iOS | 15.0 | **14.1** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Hans Kovi](https://appshunter.io/developer/1493527465) | [Janek Soomets](https://appshunter.io/developer/1315295062) |

## What reviewers say

### atom.sim

[App page](https://appshunter.io/ios/app/atomsim/id1493527466)

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

**In-app purchases:** none


### Formula Conversion

[App page](https://appshunter.io/ios/app/formula-conversion/id1586539965)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Upgrade Formula Conversion | $3.99 | one-time |


## Frequently asked questions

### Is atom.sim free?

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

### Is Formula Conversion free?

Formula Conversion is free to download, with in-app purchases available.

### Do atom.sim or Formula Conversion have ads?

Neither atom.sim nor Formula Conversion shows ads.

### Which is updated more often, atom.sim or Formula Conversion?

atom.sim ships an update every 7 months, and Formula Conversion every 26 months. Most recently, atom.sim was updated on October 11, 2026 and Formula Conversion 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.*