# Space Knowledge Quiz vs Celestia

The clearest difference is ads: Celestia at none against Space Knowledge Quiz's shown. Celestia also leads on update cadence (every 2 weeks vs every 4 months) and ratings volume (324 vs 11). On price, rating, in-app purchases and monetization model there is nothing between them.

Both are free to download. Space Knowledge Quiz sells 7 in-app purchases, starting at $1.99 per 7 days and Celestia sells 4 in-app purchases, starting at $0.99 per 7 days. Whichever you choose, the download price is not the number that matters.

Space Knowledge Quiz holds the better App Store score, 4.6 against 4.4. That said, the two scores are not equally well evidenced: Celestia has 324 ratings behind it against 11, so its average is the more settled of the two. Written reviews complicate that: 67% of Space Knowledge Quiz's written reviews are positive against 78% of Celestia's, so the app with the better star average is not the one people write more warmly about.

Space Knowledge Quiz ships an update every 4 months, Celestia every 2 weeks. The most recent releases landed on September 8, 2026 and September 25, 2026 respectively.

## The numbers

| Metric | Space Knowledge Quiz | Celestia |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.6 (11 ratings)](https://appshunter.io/ios/app/space-knowledge-quiz/id1170803086/reviews)** | [4.4 (324 ratings)](https://appshunter.io/ios/app/celestia-space-simulator/id1500434829/reviews) |
| Number of ratings | 11 | **324** |
| Positive reviews | 66.7% of reviews | **78.3% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | Yes | **No** |
| Update frequency | Every 4 months | **Every 2 weeks** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 127 MB | 545 MB |
| Requires iOS | 15.0 | 15.0 |
| Devices | iPhone, iPad, iPod | **iPhone, iPad, iPod, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [Asad Shoaib](https://appshunter.io/developer/1142302870) | [林峰 李](https://appshunter.io/developer/1186547508) |

## What reviewers say

### Space Knowledge Quiz

[App page](https://appshunter.io/ios/app/space-knowledge-quiz/id1170803086)

Test your knowledge of planets, galaxies, and space exploration with thousands of multiple-choice questions. Earn badges, track progress, and compete with friends. Ideal for students and trivia enthusiasts curious about the cosmos.

**Highlights:** Thousands of astronomy questions, Multiple-choice format, Progress tracking and statistics, Multiplayer mode, Timed tests for exam prep, Regular updates with new content

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

**In-app purchases (7)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro - No Ads & Unlock Topics | $1.99 | per 7 days |
| Pro - No Ads & Unlock Topics | $5.99 | per month |
| Pro - No Ads & Unlock Topics | $19.99 | per year |
| Half Eliminator | $0.99 | one-time |
| Reset Timer | $0.99 | one-time |
| Unlock Topics | $0.99 | one-time |
| Remove Ads | $2.99 | one-time |


### Celestia

[App page](https://appshunter.io/ios/app/celestia-space-simulator/id1500434829)

Explore the universe in real-time 3D. Visit planets, moons, star clusters, and galaxies, viewing them from any point in space and time. Customize your experience with expandable content and detailed simulations.

**Highlights:** Real-time 3D space visualization, Explore planets, moons, stars, galaxies, Accurate solar system object positions, Interactive planetarium mode, Expandable content with add-ons, Customizable celestial databases

**Features:** Game Controller support, Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Celestia PLUS (Weekly) | $0.99 | per 7 days |
| Celestia PLUS (Monthly) | $1.99 | per month |
| Celestia PLUS (Yearly) | $19.99 | per year |
| Celestia PLUS (Lifetime) | $79.99 | one-time |

**What reviewers like**

- ⭐ Realistic space simulation
- 🌌 Ability to explore galaxies and star systems
- 🔍 Detailed planet and moon textures
- 📷 Great for taking screenshots
- 🤖 Reminds users of Space Engine

**What reviewers complain about**

- 🐛 Occasional crashes and glitches
- 🌌 Limited exploration beyond Milky Way and Andromeda
- 🌍 Flat terrain on planets
- 🔍 Lack of detail on some celestial objects
- 🔒 Paywall for some features

**Reported bugs**

- Milky Way and other galaxy textures not loading properly
- Crashes when using certain add-ons
- Issues with planet and moon orbits not being accurate

**Requested features**

- Add more exoplanets and distant star systems
- Implement terrain generation for planets
- Expand to include more galaxies and the overall universe structure
- Add support for black holes, pulsars, and other exotic objects
- Improve controls and camera movement


## Frequently asked questions

### Is Space Knowledge Quiz free?

Space Knowledge Quiz is free to download, with in-app purchases available.

### Is Celestia free?

Celestia is free to download, with in-app purchases available.

### Which has better reviews, Space Knowledge Quiz or Celestia?

Space Knowledge Quiz is rated higher. Space Knowledge Quiz averages 4.6 out of 5 from 11 ratings, while Celestia averages 4.4 from 324 ratings.

### Do Space Knowledge Quiz or Celestia have ads?

Space Knowledge Quiz shows ads; Celestia does not.

### Which is updated more often, Space Knowledge Quiz or Celestia?

Space Knowledge Quiz ships an update every 4 months, and Celestia every 2 weeks. Most recently, Space Knowledge Quiz was updated on September 8, 2026 and Celestia on September 25, 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.*