# Master vs CBDR

The clearest difference is price: CBDR at Free against Master's $1.99. CBDR also leads on rating (5.0 vs 4.7) and update cadence (weekly vs fortnightly). Master's advantage is ratings volume (94 vs 4) and chart position (#93 vs unranked). On ads, in-app purchases and device support there is nothing between them.

CBDR is free to download; Master costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

CBDR holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: Master has 94 ratings behind it against 4, so its average is the more settled of the two.

Master ships an update fortnightly, CBDR weekly. The most recent releases landed on September 22, 2026 and September 18, 2026 respectively.

## The numbers

| Metric | Master | CBDR |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | [4.7 (94 ratings)](https://appshunter.io/ios/app/master-nav/id1602390396/reviews) | **[5.0 (4 ratings)](https://appshunter.io/ios/app/cbdr/id6792199258/reviews)** |
| Number of ratings | **94** | 4 |
| Positive reviews | 96.9% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Fortnightly | **Weekly** |
| Monetization | Paid | **Free** |
| Best chart rank | **#93** | — |
| Size | 117 MB | 72 MB |
| Requires iOS | **15.0** | 17.0 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Peterjohn Chisholm](https://appshunter.io/developer/1602390398) | [Sean Bowman](https://appshunter.io/developer/6792199260) |

## What reviewers say

### Master

[App page](https://appshunter.io/ios/app/master-nav/id1602390396)

**Currently charting:** #93 Top Paid · Education (US App Store)

Learn maritime navigation rules with an interactive system designed for effective retention. This app breaks down complex regulations into manageable sections with visual aids and mnemonics. It revisits incorrect answers and provides instant graphical feedback, making the learning process intuitive and efficient.

**Highlights:** Interactive learning system, Step-by-step rule guidance, Mnemonics and memory aids, Interactive visuals, Graphical feedback on answers, Practice section with progress tracking

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

**In-app purchases:** none


### CBDR

[App page](https://appshunter.io/ios/app/cbdr/id6792199258)

This app trains junior deck officers and watchstanders in essential radar watch skills, including contact evaluation, COLREGS classification, and generating contact reports. It features a live radar scope, generated scenarios for various navigation situations, and drills for recognition and maneuvering.

**Highlights:** Live radar scope with vectors and trails, Generated navigation scenarios, COLREGS classification, Contact report scoring, Maneuvering board drills, Recognition drills, USCG Rules of the Road test bank, Offline group testing

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

**In-app purchases:** none


## Frequently asked questions

### Is Master free?

Master costs $1.99, with no in-app purchases.

### Is CBDR free?

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

### Which has better reviews, Master or CBDR?

CBDR is rated higher. Master averages 4.7 out of 5 from 94 ratings, while CBDR averages 5.0 from 4 ratings.

### Do Master or CBDR have ads?

Neither Master nor CBDR shows ads.

### Which is updated more often, Master or CBDR?

Master ships an update fortnightly, and CBDR weekly. Most recently, Master was updated on September 22, 2026 and CBDR on September 18, 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.*