# ACR Product App vs Rule Master

The clearest difference is price: ACR Product App at Free against Rule Master's $9.99. ACR Product App also leads on device support (3 vs 1). Rule Master's advantage is rating (4.8 vs 1.7) and review sentiment (43% vs 22%). On update cadence, ads, in-app purchases and iOS requirement there is nothing between them.

ACR Product App is free to download; Rule Master costs $9.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Rule Master holds the better App Store score, 4.8 against 1.7. That said, the two scores are not equally well evidenced: Rule Master has 297 ratings behind it against 36, so its average is the more settled of the two. Written reviews point the same way: 22% of ACR Product App's written reviews are positive against 43% of Rule Master's.

ACR Product App ships an update every 2 months, Rule Master every 3 months. The most recent releases landed on November 3, 2026 and November 7, 2026 respectively.

## The numbers

| Metric | ACR Product App | Rule Master |
| --- | --- | --- |
| Price | **Free** | $9.99 |
| Rating | [1.7 (36 ratings)](https://appshunter.io/ios/app/acr-product-app/id1458864580/reviews) | **[4.8 (297 ratings)](https://appshunter.io/ios/app/rule-master/id1617543595/reviews)** |
| Number of ratings | 36 | **297** |
| Positive reviews | 21.7% of reviews | **42.9% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 2 months** | Every 3 months |
| Monetization | **Free** | Free with in-app purchases |
| Best chart rank | — | **#29** |
| Size | 113 MB | 13 MB |
| Requires iOS | **15.0** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Ocean Signal Limited](https://appshunter.io/developer/1453183712) | [Universal Queue LLC](https://appshunter.io/developer/1577058225) |

## What reviewers say

### ACR Product App

[App page](https://appshunter.io/ios/app/acr-product-app/id1458864580)

Access Class B AIS and Emergency PLB/EPIRB data. View live AIS targets, check distress beacon details, and monitor battery status via NFC or WiFi. Configure your AIS with vessel information.

**Highlights:** View live AIS targets, Check PLB/EPIRB distress beacon details, Monitor beacon operation time and battery condition via NFC, Configure Class B AIS with vessel details via WiFi, Access ACR CB2 WiFi connection for AIS data

**Features:** macOS Compatibility

**In-app purchases:** none


### Rule Master

[App page](https://appshunter.io/ios/app/rule-master/id1617543595)

**Currently charting:** #29 Top Paid · Navigation (US App Store)

Master maritime navigation rules with this comprehensive quiz app. It offers extensive question banks, custom filters, and detailed progress tracking for both new and experienced sailors. Generate custom exams and access a digital handbook for efficient learning and exam preparation.

**Highlights:** 10,000+ question-answer combinations, Custom question filters, Fill-in-the-blank questions, Offline capability, Exam PDF generation, Digital Navigation Rules handbook, Progress tracking and statistics

**Features:** Vision Pro support

**In-app purchases:** none

**What reviewers like**

- 👍 User friendly and easy to navigate
- 📚 Great information for studying and review
- 💯 Helpful for exam preparation and confidence
- ✨ Beautifully designed and functional app
- ✅ Worth a download

**What reviewers complain about**

- 💰 Free apps are just as good
- 🐛 Questions disappear off the screen
- 🤏 Diagrams are too small to see details
- ❓ Incomplete questions with missing text
- ⚠️ Some answers are not 100% accurate

**Reported bugs**

- Questions disappear off the bottom of the screen
- Diagrams are too small to identify vessels
- Some questions have character limits over the margin
- App doesn't display quiz and verbatim in a usable manner
- Incomplete questions showing three dots (...)

**Requested features**

- Link relevant COLREG rule when answering correctly and incorrectly
- Expand subjects to include chemistry or history
- Improvements in tracking missed questions for training
- Display full question text when it's cut off


## Frequently asked questions

### Is ACR Product App free?

ACR Product App is free to download, with no in-app purchases.

### Is Rule Master free?

Rule Master costs $9.99, with no in-app purchases.

### Which has better reviews, ACR Product App or Rule Master?

Rule Master is rated higher. ACR Product App averages 1.7 out of 5 from 36 ratings, while Rule Master averages 4.8 from 297 ratings.

### Do ACR Product App or Rule Master have ads?

Neither ACR Product App nor Rule Master shows ads.

### Which is updated more often, ACR Product App or Rule Master?

ACR Product App ships an update every 2 months, and Rule Master every 3 months. Most recently, ACR Product App was updated on November 3, 2026 and Rule Master on November 7, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*