# Forest Books vs Periodic

The clearest difference is ads: Forest Books at none against Periodic's shown. Forest Books also leads on iOS requirement (13.4 vs 15.1). Periodic's advantage is update cadence (every 5 weeks vs every 3 months). On price, in-app purchases and device support there is nothing between them.

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

Forest Books ships an update every 3 months, Periodic every 5 weeks. The most recent releases landed on October 10, 2026 and October 12, 2026 respectively.

## The numbers

| Metric | Forest Books | Periodic |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 3 months | **Every 5 weeks** |
| Size | 61 MB | 35 MB |
| Requires iOS | **13.4** | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Dana Czencz](https://appshunter.io/developer/1406444200) | [Om Prakash Chapagain](https://appshunter.io/developer/1618620262) |

## What reviewers say

### Forest Books

[App page](https://appshunter.io/ios/app/forest-books/id1406444891)

**Features:** macOS Compatibility

**In-app purchases:** none


### Periodic

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

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

**In-app purchases:** none


## Frequently asked questions

### Is Forest Books free?

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

### Is Periodic free?

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

### Do Forest Books or Periodic have ads?

Periodic shows ads; Forest Books does not.

### Which is updated more often, Forest Books or Periodic?

Forest Books ships an update every 3 months, and Periodic every 5 weeks. Most recently, Forest Books was updated on October 10, 2026 and Periodic on October 12, 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.*