# Inside Earth vs Cat Probability Roulette

The clearest difference is in-app purchases: Inside Earth at none against Cat Probability Roulette's 1. Inside Earth also leads on ads (none vs shown) and update cadence (fortnightly vs every 2 months). On price and device support there is nothing between them.

Both are free to download. Cat Probability Roulette sells 1 one-off in-app purchase. Inside Earth asks for nothing beyond the download.

Inside Earth ships an update fortnightly, Cat Probability Roulette every 2 months. The most recent releases landed on November 3, 2026 and November 5, 2026 respectively.

## The numbers

| Metric | Inside Earth | Cat Probability Roulette |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (81 ratings)](https://appshunter.io/ios/app/inside-earth-crust-to-core/id1600729183/reviews)** | — |
| Number of ratings | **81** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | **Fortnightly** | Every 2 months |
| Monetization | Free | — |
| Size | 190 MB | 138 MB |
| Requires iOS | **13.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Sebastian Andre](https://appshunter.io/developer/1131259796) | [Yusuke Okada](https://appshunter.io/developer/1793725878) |

## What reviewers say

### Inside Earth

[App page](https://appshunter.io/ios/app/inside-earth-crust-to-core/id1600729183)

Explore the Earth's interior by virtually peeling back its layers. Understand the composition of the crust, mantle, and core. Learn about tectonic plates, volcanism, and earthquakes.

**Highlights:** Interactive layer peeling, Tectonic plate visualization, Volcanism and earthquake explanation, Compositional learning, Geological process discovery

**In-app purchases:** none


### Cat Probability Roulette

[App page](https://appshunter.io/ios/app/cat-probability-roulette/id6754866024)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $0.49 | one-time |


## Frequently asked questions

### Is Inside Earth free?

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

### Is Cat Probability Roulette free?

Cat Probability Roulette is free to download, with in-app purchases available.

### Do Inside Earth or Cat Probability Roulette have ads?

Cat Probability Roulette shows ads; Inside Earth does not.

### Which is updated more often, Inside Earth or Cat Probability Roulette?

Inside Earth ships an update fortnightly, and Cat Probability Roulette every 2 months. Most recently, Inside Earth was updated on November 3, 2026 and Cat Probability Roulette on November 5, 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.*