# Cosmology vs Stars Units Sizes Objects

The clearest difference is rating: Cosmology at 4.7 against Stars Units Sizes Objects's 4.2. Cosmology also leads on ads (none vs shown) and ratings volume (505 vs 5). On price, in-app purchases, device support and iOS requirement there is nothing between them.

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

Cosmology holds the better App Store score, 4.7 against 4.2. That said, the two scores are not equally well evidenced: Cosmology has 505 ratings behind it against 5, so its average is the more settled of the two. Written reviews point the same way: 89% of Cosmology's written reviews are positive against 80% of Stars Units Sizes Objects's.

Cosmology ships an update monthly, Stars Units Sizes Objects every 4 months. The most recent releases landed on October 15, 2026 and September 22, 2026 respectively.

## The numbers

| Metric | Cosmology | Stars Units Sizes Objects |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (505 ratings)](https://appshunter.io/ios/app/cosmology/id1028872453/reviews)** | [4.2 (5 ratings)](https://appshunter.io/ios/app/stars-units-sizes-objects/id1576148571/reviews) |
| Number of ratings | **505** | 5 |
| Positive reviews | **88.6% of reviews** | 80.0% of reviews |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | **Monthly** | Every 4 months |
| Monetization | **Free** | Ad-supported |
| Size | 190 MB | 124 MB |
| Requires iOS | 11.0 | 11.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Aaron Day](https://appshunter.io/developer/1028872452) | [Mudarmeen Munlin](https://appshunter.io/developer/1348165664) |

## What reviewers say

### Cosmology

[App page](https://appshunter.io/ios/app/cosmology/id1028872453)

Explore the universe with stunning high-resolution images of celestial bodies. Journey through space, visiting planets and their moons, while learning about the evolution of space, time, and matter. Ponder the profound mysteries of existence.

**Highlights:** High-resolution images of planets, nebulae, and galaxies, Interactive space travel to planets and moons, Learn about the evolution of space, time, and matter, Expert narration by Dr. Aaron Day, Exploration of existential mysteries of the universe

**In-app purchases:** none

**What reviewers like**

- 🌟 Stunning, beautiful astrophotography images
- 📚 Educational content about space and universe
- 👍 Easy to use and understand interface
- 🎥 Informative videos and interactive features
- 🗺️ Interactive map for exploring cosmic scales

**What reviewers complain about**

- 🐛 Image interference/technical glitches
- 📖 Shallow explanations for non-experts
- ⚠️ Limited educational depth compared to NASA app
- 🤔 Big Bang theory focus may conflict with religious beliefs
- ❌ Incomplete sections (Milky Way, Island Universe)

**Reported bugs**

- Image display interference/hacking concerns
- App feels incomplete in certain sections

**Requested features**

- More interactive activities and engagement features
- Text-to-speech functionality
- More detailed explanations for beginner-level users
- Additional sub-categories and content sections
- Regular updates with current astronomical images


### 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 Cosmology free?

Cosmology 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, Cosmology or Stars Units Sizes Objects?

Cosmology is rated higher. Cosmology averages 4.7 out of 5 from 505 ratings, while Stars Units Sizes Objects averages 4.2 from 5 ratings.

### Do Cosmology or Stars Units Sizes Objects have ads?

Stars Units Sizes Objects shows ads; Cosmology does not.

### Which is updated more often, Cosmology or Stars Units Sizes Objects?

Cosmology ships an update monthly, and Stars Units Sizes Objects every 4 months. Most recently, Cosmology was updated on October 15, 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.*