# Mars Book vs Discover Mars

The clearest difference is update cadence: Discover Mars at monthly against Mars Book's every 13 months. Mars Book's advantage is iOS requirement (9.0 vs 13.0). 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, Discover Mars monthly. The most recent releases landed on October 26, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Mars Book | Discover Mars |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (12 ratings)](https://appshunter.io/ios/app/discover-mars/id1550710909/reviews)** |
| Number of ratings | — | **12** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 13 months | **Monthly** |
| Monetization | — | Free |
| Size | 14 MB | 8 MB |
| Requires iOS | **9.0** | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Vixen Co.,Ltd.](https://appshunter.io/developer/536188843) | [Manthan B Thakkar](https://appshunter.io/developer/1550710911) |

## What reviewers say

### Mars Book

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

**In-app purchases:** none


### Discover Mars

[App page](https://appshunter.io/ios/app/discover-mars/id1550710909)

Explore stunning, high-definition images captured on Mars by NASA rovers. View the latest photos, zoom in for detail, and learn fascinating facts about the Red Planet's atmosphere, gravity, and temperature.

**Highlights:** View latest Mars rover images, Slideshow mode for full-screen viewing, Zoom into high-definition photos, Save images to your device, Explore Mars' atmosphere, gravity, and temperature

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Mars Book free?

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

### Is Discover Mars free?

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

### Do Mars Book or Discover Mars have ads?

Neither Mars Book nor Discover Mars shows ads.

### Which is updated more often, Mars Book or Discover Mars?

Mars Book ships an update every 13 months, and Discover Mars monthly. Most recently, Mars Book was updated on October 26, 2026 and Discover Mars on October 24, 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.*