# Neptune vs CA'Sim

The clearest difference is in-app purchases: Neptune at none against CA'Sim's 4. Neptune also leads on iOS requirement (15.0 vs 18.6). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. CA'Sim sells 4 in-app purchases, starting at $0.99 per month. Neptune asks for nothing beyond the download.

Neptune ships an update every 4 days, CA'Sim weekly. The most recent releases landed on October 10, 2026 and October 11, 2026 respectively.

## The numbers

| Metric | Neptune | CA'Sim |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (15 ratings)](https://appshunter.io/ios/app/neptune-navigation-rules/id6756641315/reviews)** | — |
| Number of ratings | **15** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 4 days** | Weekly |
| Monetization | Free | — |
| Size | 96 MB | 6 MB |
| Requires iOS | **15.0** | 18.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Brice Brown](https://appshunter.io/developer/1555846025) | [Jatuphol Jaturapat](https://appshunter.io/developer/1788860463) |

## What reviewers say

### Neptune

[App page](https://appshunter.io/ios/app/neptune-navigation-rules/id6756641315)

Prepare for USCG COLREG and OOD exams with a comprehensive study system. Features AI tutoring, interactive 3D visuals for lights and shapes, and a complete question bank with intelligent test modes and progress tracking.

**Highlights:** AI-powered tutor for rule explanations, Interactive 3D lights and shapes trainer, Official USCG question bank, Verbatim memory trainer, Intelligent exam simulator modes, Advanced progress tracking, Offline study capability

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

**In-app purchases:** none


### CA'Sim

[App page](https://appshunter.io/ios/app/casim/id6758004211)

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock All Features. (1 Month) | $0.99 | per month |
| Unlock All Features. (3 Months) | $2.99 | per 3 months |
| Unlock All Features. (1 Year) | $7.99 | per year |
| Lifetime Access | $17.99 | one-time |


## Frequently asked questions

### Is Neptune free?

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

### Is CA'Sim free?

CA'Sim is free to download, with in-app purchases available.

### Do Neptune or CA'Sim have ads?

Neither Neptune nor CA'Sim shows ads.

### Which is updated more often, Neptune or CA'Sim?

Neptune ships an update every 4 days, and CA'Sim weekly. Most recently, Neptune was updated on October 10, 2026 and CA'Sim on October 11, 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.*