# Earth's Core vs Stars Units Sizes Objects

The clearest difference is ads: Earth's Core at none against Stars Units Sizes Objects's shown. Earth's Core also leads on review sentiment (100% vs 80%) and monetization model (free vs ad-supported). Stars Units Sizes Objects's advantage is update cadence (every 4 months vs every 70 months). On price, rating, ratings volume and in-app purchases there is nothing between them.

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

On the App Store both sit at effectively the same score — 4.3 for Earth's Core against 4.2 for Stars Units Sizes Objects. Both are backed by a comparable volume of ratings — 4 and 5 respectively. Written reviews are what separate them: 100% of Earth's Core's written reviews are positive against 80% of Stars Units Sizes Objects's.

Earth's Core ships an update every 70 months, Stars Units Sizes Objects every 4 months. The most recent releases landed on September 30, 2026 and September 22, 2026 respectively.

## The numbers

| Metric | Earth's Core | Stars Units Sizes Objects |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.3 (4 ratings)](https://appshunter.io/ios/app/earths-core/id1220835186/reviews)** | [4.2 (5 ratings)](https://appshunter.io/ios/app/stars-units-sizes-objects/id1576148571/reviews) |
| Number of ratings | 4 | **5** |
| Positive reviews | **100.0% of reviews** | 80.0% of reviews |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 70 months | **Every 4 months** |
| Monetization | **Free** | Ad-supported |
| Size | 54 MB | 124 MB |
| Requires iOS | 12.0 | **11.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Celestial Dynamics AG](https://appshunter.io/developer/997250789) | [Mudarmeen Munlin](https://appshunter.io/developer/1348165664) |

## What reviewers say

### Earth's Core

[App page](https://appshunter.io/ios/app/earths-core/id1220835186)

Explore the internal structure of our planet with a detailed view of Earth's layers. Discover the composition, temperature, and depth of each section, from the crust to the core. This educational tool provides a fascinating look beneath your feet.

**Highlights:** Visualize Earth's internal structure, Explore planet layers, Discover layer temperatures, Learn layer depths, Detailed look inside the planet

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

**In-app purchases:** none


### Stars Units Sizes Objects

[App page](https://appshunter.io/ios/app/stars-units-sizes-objects/id1576148571)

Explore the vastness of the universe, from the smallest particles to the largest cosmic structures. Compare object sizes, view detailed images, and perform unit conversions across a wide range of astronomical scales. Learn about stars, galaxies, and the incredible distances between them.

**Highlights:** Compare object sizes, View object images, Pinch/Zoom and Pan images, Unit conversion for distances, Explore scales from Planck length to observable universe, Learn about stars and galaxies

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Earth's Core free?

Earth's Core is free to download, with no in-app purchases.

### Is Stars Units Sizes Objects free?

Stars Units Sizes Objects is free to download, with no in-app purchases.

### Which has better reviews, Earth's Core or Stars Units Sizes Objects?

Earth's Core is rated higher. Earth's Core averages 4.3 out of 5 from 4 ratings, while Stars Units Sizes Objects averages 4.2 from 5 ratings.

### Do Earth's Core or Stars Units Sizes Objects have ads?

Stars Units Sizes Objects shows ads; Earth's Core does not.

### Which is updated more often, Earth's Core or Stars Units Sizes Objects?

Earth's Core ships an update every 70 months, and Stars Units Sizes Objects every 4 months. Most recently, Earth's Core was updated on September 30, 2026 and Stars Units Sizes Objects on September 22, 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.*