# atom.sim vs Periodic

The clearest difference is ads: atom.sim at none against Periodic's shown. Periodic's advantage is update cadence (every 5 weeks vs every 7 months). On price, in-app purchases, device support and iOS requirement there is nothing between them.

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

atom.sim ships an update every 7 months, Periodic every 5 weeks. The most recent releases landed on September 10, 2026 and May 16, 2026 respectively.

## The numbers

| Metric | atom.sim | Periodic |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 7 months | **Every 5 weeks** |
| Size | 78 MB | 35 MB |
| Requires iOS | **15.0** | 15.1 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Hans Kovi](https://appshunter.io/developer/1493527465) | [Om Prakash Chapagain](https://appshunter.io/developer/1618620262) |

## What reviewers say

### atom.sim

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

**Features:** macOS Compatibility

**In-app purchases:** none


### Periodic

[App page](https://appshunter.io/ios/app/periodic-table-elements/id1628647298)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is atom.sim free?

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

### Is Periodic free?

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

### Do atom.sim or Periodic have ads?

Periodic shows ads; atom.sim does not.

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

atom.sim ships an update every 7 months, and Periodic every 5 weeks. Most recently, atom.sim was updated on September 10, 2026 and Periodic on May 16, 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.*