# Solar System 3D vs Number Line, by MLC

The clearest difference is rating: Number Line, by MLC at 4.4 against Solar System 3D's 3.7. Number Line, by MLC also leads on in-app purchases (none vs 4). Solar System 3D's advantage is update cadence (every 2 weeks vs every 13 months) and device support (3 vs 1). On price, review sentiment, ratings volume and ads there is nothing between them.

Both are free to download. Solar System 3D sells 4 one-off in-app purchases. Number Line, by MLC asks for nothing beyond the download.

Number Line, by MLC holds the better App Store score, 4.4 against 3.7. Both are backed by a comparable volume of ratings — 31 and 15 respectively. Written reviews complicate that: 68% of Solar System 3D's written reviews are positive against 67% of Number Line, by MLC's, so the app with the better star average is not the one people write more warmly about.

Solar System 3D ships an update every 2 weeks, Number Line, by MLC every 13 months. Both last shipped on November 1, 2026.

## The numbers

| Metric | Solar System 3D | Number Line, by MLC |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.7 (31 ratings)](https://appshunter.io/ios/app/solar-system-3d/id681687550/reviews) | **[4.4 (15 ratings)](https://appshunter.io/ios/app/number-line-by-mlc/id751816884/reviews)** |
| Number of ratings | **31** | 15 |
| Positive reviews | **67.9% of reviews** | 66.7% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 2 weeks** | Every 13 months |
| Monetization | Free with in-app purchases | **Free** |
| Size | 54 MB | 7 MB |
| Requires iOS | **4.3** | 16.1 |
| Devices | **iPhone, iPad, iPod** | iPad |
| Age rating | 4+ | 4+ |
| Developer | [ZHIREN GUAN](https://appshunter.io/developer/400879572) | [The Math Learning Center](https://appshunter.io/developer/1542700905) |

## What reviewers say

### Solar System 3D

[App page](https://appshunter.io/ios/app/solar-system-3d/id681687550)

Explore our solar system in stunning 3D. Navigate through planets, moons, and celestial bodies, accessing detailed Wikipedia information. Experience realistic simulations of Earth's seasons, day-night cycles, and planetary motion.

**Highlights:** 3D space navigation, Full solar system model, Wikipedia information, Spinning and orbiting simulation, Earth's seasonal tilt, Day-night simulation, Real scale factors

**Features:** macOS Compatibility

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $0.99 | one-time |
| High Definition Texture | $0.99 | one-time |
| Wallpaper Screenshot | $0.99 | one-time |
| Special Package Offer | $0.99 | one-time |


### Number Line, by MLC

[App page](https://appshunter.io/ios/app/number-line-by-mlc/id751816884)

This app allows students to visualize number sequences and demonstrate mathematical strategies. It supports various number types and offers tools for annotation, problem-solving, and sharing work. Ideal for elementary classrooms and iPad learning environments.

**Highlights:** Visualize number sequences, Demonstrate counting, adding, subtracting, multiplying, dividing, Use whole numbers, fractions, decimals, or negative numbers, Add custom tick marks and labels, Hide and reveal numbers and jumps, Annotation and drawing tools, Save and share work

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Solar System 3D free?

Solar System 3D is free to download, with in-app purchases available.

### Is Number Line, by MLC free?

Number Line, by MLC is free to download, with no in-app purchases.

### Which has better reviews, Solar System 3D or Number Line, by MLC?

Number Line, by MLC is rated higher. Solar System 3D averages 3.7 out of 5 from 31 ratings, while Number Line, by MLC averages 4.4 from 15 ratings.

### Do Solar System 3D or Number Line, by MLC have ads?

Neither Solar System 3D nor Number Line, by MLC shows ads.

### Which is updated more often, Solar System 3D or Number Line, by MLC?

Solar System 3D ships an update every 2 weeks, and Number Line, by MLC every 13 months. Most recently, Solar System 3D was updated on November 1, 2026 and Number Line, by MLC on November 1, 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.*