# Mars Book vs Sample for Science

The clearest difference is update cadence: Sample for Science at every 6 weeks against Mars Book's every 13 months. Mars Book's advantage is iOS requirement (9.0 vs 12.0). On price, ads, 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.

Mars Book ships an update every 13 months, Sample for Science every 6 weeks. The most recent releases landed on October 26, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | Mars Book | Sample for Science |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 13 months | **Every 6 weeks** |
| Size | 14 MB | 58 MB |
| Requires iOS | **9.0** | 12.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | +4 |
| Developer | [Vixen Co.,Ltd.](https://appshunter.io/developer/536188843) | [Universidade Federal Fluminense - UFF](https://appshunter.io/developer/739312311) |

## What reviewers say

### Mars Book

[App page](https://appshunter.io/ios/app/mars-book/id1342509724)

**In-app purchases:** none


### Sample for Science

[App page](https://appshunter.io/ios/app/sample-for-science/id6470819452)

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

**In-app purchases:** none


## Frequently asked questions

### Is Mars Book free?

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

### Is Sample for Science free?

Sample for Science is free to download, with no in-app purchases.

### Do Mars Book or Sample for Science have ads?

Neither Mars Book nor Sample for Science shows ads.

### Which is updated more often, Mars Book or Sample for Science?

Mars Book ships an update every 13 months, and Sample for Science every 6 weeks. Most recently, Mars Book was updated on October 26, 2026 and Sample for Science on October 30, 2026.

---

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