---
title: "Master-Nav - Reviews, Revenue and Downloads in United States | Apple App Store"
description: "Master-Nav is a progressive COLREGS learning system developed by a Master Mariner. The COLREGS are notoriously difficult to learn and retain — Master-Nav makes it significantly easier through an inter"
---

# Master-Nav — United States
> NAV RULES - the easy way!

![Master-Nav App Icon](https://is1-ssl.mzstatic.com/image/thumb/Purple221/v4/52/a3/99/52a3993b-728b-b64b-dd7d-c3c6a4161325/AppIcon-0-0-1x_U007emarketing-0-8-0-85-220.png/434x0w.png)

**Developer:** [Peterjohn Chisholm](https://apptail.io/developer/peterjohn-chisholm-xgab)
**Category:** Education
**Rating:** 4.7/5 (86 ratings)
**Price:** Free
**Bundle ID:** eu.pjcc.NavMaster
**Store:** Apple App Store
**Country:** United States
**Version:** 1.46 (released 2026-04-01)
**Original Release:** 2022-01-08
**Languages:** English

**App Store Link:** [Download on Apple App Store](https://apps.apple.com/us/app/app/id1602390396)
**AppTail Page:** [https://apptail.io/app/master-nav-VYXc/united-states](https://apptail.io/app/master-nav-VYXc/united-states)

## Master-Nav Description
Master-Nav is a progressive COLREGS learning system developed by a Master Mariner. The COLREGS are notoriously difficult to learn and retain — Master-Nav makes it significantly easier through an interactive system built around how your brain actually works.

Instead of guessing through random question banks, Master-Nav guides you step by step through every rule from start to finish. Wrong answers are revisited until the rules stick — properly.

Complex regulations are broken down into learnable chunks — bite-sized sections supported by mnemonics, memory aids and interactive visuals designed around how the brain actually retains information.

Every incorrect answer is shown graphically alongside the correct one — immediately clear, no confusion. And with a single tap, the relevant COLREGS rule is accessible from any question at any time.

Master-Nav covers COLREGS Parts A to D — General, Steering & Sailing, Lights & Shapes and Sound & Light Signals — plus Annex IV Distress Signals. Over 1000 questions in multiple formats, with a dedicated Practice Section that tracks right, wrong and unanswered so you always know where to focus.

COLREGS — the easy way.

## Master-Nav Screenshots
- [Screenshot 1](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/ee/fb/b5/eefbb52e-42f8-6325-54a4-812ba4eeea22/01.png/1284x2778.png)
- [Screenshot 2](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource221/v4/81/0d/8d/810d8d68-bcea-79de-6412-727551226c6a/04.png/1284x2778.png)
- [Screenshot 3](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource221/v4/41/86/bd/4186bde8-a46b-4f4a-3e1a-ea5b886bd5d2/05.png/1284x2778.png)
- [Screenshot 4](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/30/65/34/306534a6-8341-a9b5-f597-8a5a4a55de34/03.png/1284x2778.png)
- [Screenshot 5](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/93/50/72/9350722b-53e7-c318-cc04-820cae73ad87/09.png/1284x2778.png)
- [Screenshot 6](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource221/v4/3b/bc/28/3bbc282b-447f-6550-338a-30767eaa1e3d/07.png/1284x2778.png)
- [Screenshot 7](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource221/v4/d5/a8/71/d5a871b2-5bac-0ae9-bb98-36304e0e9971/02.png/1284x2778.png)
- [Screenshot 8](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/ee/05/3a/ee053af1-3e49-2a0e-9d59-0e5b7b54db9b/06.png/1284x2778.png)
- [Screenshot 9](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/ac/3c/4e/ac3c4e3c-ed21-54bc-6c3d-259e259a44c7/08.png/1284x2778.png)

## Master-Nav Rating Breakdown in United States
- 5 stars: 72 (84%)
- 4 stars: 10 (12%)
- 3 stars: 1 (1%)
- 2 stars: 1 (1%)
- 1 stars: 2 (2%)

## Master-Nav Reviews in United States

### ***** "Great Refresher and Prep Tool"
I’m getting ready to start training for my next assignment on a ship. This is an easy to use tool. I was just looking for the COLREGS test questions, but the Review modules are extremely helpful. It’s like having a high level Maritime Rules of the Road instructor on your phone.
-- SWO4Life, 2024-11-10

### ***** "Great for SWOs going to BDOC"
I couldn’t just read COLREGS and make it stick to my brain for sheee, thank god for this app and the creators of this dynamic way of memorizing rule by rule. Because if your going to be navigating a multi million-billion dollar ship make sure you have this memorized to the T!
-- Youngchepe, 2024-10-12

### ***** "Great app"
Easy to navigate, easy to understand, covers all the key elements needed to prep for the exam.
-- NicC1975, 2022-02-12

[View all Master-Nav reviews and detailed analytics on AppTail](https://apptail.io/account/signup?utm_campaign=ai-crawl&utm_content=reviews)


## Master-Nav Store Rankings
| Chart | Country | Category | Rank |
|-------|---------|----------|------|
| Top Paid | Italy | Education | #5 |
| Top Paid | Philippines | Education | #27 |
| Top Paid | Italy | Overall | #36 |
| Top Paid | United Kingdom | Education | #59 |
| Top Paid | Australia | Education | #85 |
| Top Paid | Romania | Education | #95 |
| Top Paid | South Africa | Education | #96 |
| Top Paid | Greece | Education | #120 |
| Top Paid | India | Education | #127 |
| Top Paid | Canada | Education | #132 |
| Top Paid | Nigeria | Education | #138 |
| Top Paid | Czechia | Education | #198 |
| Top Paid | Philippines | Overall | #199 |
| Top Paid | United Arab Emirates | Education | #203 |
| Top Paid | United States | Education | #212 |
| Top Paid | Singapore | Education | #217 |
| Top Paid | Ukraine | Education | #236 |
| Top Paid | Ireland | Education | #254 |
| Top Paid | Poland | Education | #257 |
| Top Paid | Malaysia | Education | #272 |
| Top Paid | Saudi Arabia | Education | #282 |
| Top Paid | United Kingdom | Overall | #310 |
| Top Paid | Finland | Education | #353 |
| Top Paid | Spain | Education | #354 |
| Top Paid | New Zealand | Education | #377 |
| Top Paid | Hungary | Education | #382 |
| Top Paid | Egypt | Education | #407 |
| Top Paid | Belgium | Education | #420 |
| Top Paid | Netherlands | Education | #429 |
| Top Paid | Indonesia | Education | #453 |

## Master-Nav Discovered Keywords
- rules of the road
- colregs


## Master-Nav Available In
- [United Kingdom](https://apptail.io/app/master-nav-VYXc/united-kingdom)
- [United States](https://apptail.io/app/master-nav-VYXc/united-states)
- [Australia](https://apptail.io/app/master-nav-VYXc/australia)
- [Canada](https://apptail.io/app/master-nav-VYXc/canada)
- [South Africa](https://apptail.io/app/master-nav-VYXc/south-africa)
- [France](https://apptail.io/app/master-nav-VYXc/france)
- [Philippines](https://apptail.io/app/master-nav-VYXc/philippines)
- [India](https://apptail.io/app/master-nav-VYXc/india)
- [Germany](https://apptail.io/app/master-nav-VYXc/germany)
- [Italy](https://apptail.io/app/master-nav-VYXc/italy)
- [Sweden](https://apptail.io/app/master-nav-VYXc/sweden)
- [Spain](https://apptail.io/app/master-nav-VYXc/spain)
- [Malaysia](https://apptail.io/app/master-nav-VYXc/malaysia)
- [Netherlands](https://apptail.io/app/master-nav-VYXc/netherlands)
- [United Arab Emirates](https://apptail.io/app/master-nav-VYXc/united-arab-emirates)
- [New Zealand](https://apptail.io/app/master-nav-VYXc/new-zealand)
- [Hungary](https://apptail.io/app/master-nav-VYXc/hungary)
- [Finland](https://apptail.io/app/master-nav-VYXc/finland)
- [Greece](https://apptail.io/app/master-nav-VYXc/greece)
- [Czechia](https://apptail.io/app/master-nav-VYXc/czechia)
- [Thailand](https://apptail.io/app/master-nav-VYXc/thailand)
- [Türkiye](https://apptail.io/app/master-nav-VYXc/turkey)
- [Ukraine](https://apptail.io/app/master-nav-VYXc/ukraine)
- [Austria](https://apptail.io/app/master-nav-VYXc/austria)
- [Argentina](https://apptail.io/app/master-nav-VYXc/argentina)
- [Singapore](https://apptail.io/app/master-nav-VYXc/singapore)
- [Egypt](https://apptail.io/app/master-nav-VYXc/egypt)
- [Norway](https://apptail.io/app/master-nav-VYXc/norway)
- [Switzerland](https://apptail.io/app/master-nav-VYXc/switzerland)
- [Mexico](https://apptail.io/app/master-nav-VYXc/mexico)
- [Brazil](https://apptail.io/app/master-nav-VYXc/brazil)
- [Taiwan](https://apptail.io/app/master-nav-VYXc/taiwan)
- [Kenya](https://apptail.io/app/master-nav-VYXc/kenya)
- [Malta](https://apptail.io/app/master-nav-VYXc/malta)
- [Vietnam](https://apptail.io/app/master-nav-VYXc/vietnam)
- [Poland](https://apptail.io/app/master-nav-VYXc/poland)
- [Belgium](https://apptail.io/app/master-nav-VYXc/belgium)
- [Bulgaria](https://apptail.io/app/master-nav-VYXc/bulgaria)
- [Russia](https://apptail.io/app/master-nav-VYXc/russia)
- [Ireland](https://apptail.io/app/master-nav-VYXc/ireland)
- [North Macedonia](https://apptail.io/app/master-nav-VYXc/north-macedonia)
- [Azerbaijan](https://apptail.io/app/master-nav-VYXc/azerbaijan)
- [Brunei](https://apptail.io/app/master-nav-VYXc/brunei)
- [Belarus](https://apptail.io/app/master-nav-VYXc/belarus)
- [Chile](https://apptail.io/app/master-nav-VYXc/chile)
- [China](https://apptail.io/app/master-nav-VYXc/china)
- [Colombia](https://apptail.io/app/master-nav-VYXc/colombia)
- [Denmark](https://apptail.io/app/master-nav-VYXc/denmark)
- [Dominican Republic](https://apptail.io/app/master-nav-VYXc/dominican-republic)
- [Algeria](https://apptail.io/app/master-nav-VYXc/algeria)
- [Ecuador](https://apptail.io/app/master-nav-VYXc/ecuador)
- [Estonia](https://apptail.io/app/master-nav-VYXc/estonia)
- [Hong Kong SAR China](https://apptail.io/app/master-nav-VYXc/hong-kong)
- [Croatia](https://apptail.io/app/master-nav-VYXc/croatia)
- [Indonesia](https://apptail.io/app/master-nav-VYXc/indonesia)
- [Israel](https://apptail.io/app/master-nav-VYXc/israel)
- [Iceland](https://apptail.io/app/master-nav-VYXc/iceland)
- [Japan](https://apptail.io/app/master-nav-VYXc/japan)
- [South Korea](https://apptail.io/app/master-nav-VYXc/south-korea)
- [Kuwait](https://apptail.io/app/master-nav-VYXc/kuwait)
- [Kazakhstan](https://apptail.io/app/master-nav-VYXc/kazakhstan)
- [Lebanon](https://apptail.io/app/master-nav-VYXc/lebanon)
- [Sri Lanka](https://apptail.io/app/master-nav-VYXc/sri-lanka)
- [Lithuania](https://apptail.io/app/master-nav-VYXc/lithuania)
- [Luxembourg](https://apptail.io/app/master-nav-VYXc/luxembourg)
- [Latvia](https://apptail.io/app/master-nav-VYXc/latvia)
- [Nigeria](https://apptail.io/app/master-nav-VYXc/nigeria)
- [Nepal](https://apptail.io/app/master-nav-VYXc/nepal)
- [Peru](https://apptail.io/app/master-nav-VYXc/peru)
- [Pakistan](https://apptail.io/app/master-nav-VYXc/pakistan)
- [Portugal](https://apptail.io/app/master-nav-VYXc/portugal)
- [Romania](https://apptail.io/app/master-nav-VYXc/romania)
- [Saudi Arabia](https://apptail.io/app/master-nav-VYXc/saudi-arabia)
- [Slovenia](https://apptail.io/app/master-nav-VYXc/slovenia)
- [Slovakia](https://apptail.io/app/master-nav-VYXc/slovakia)
- [Tunisia](https://apptail.io/app/master-nav-VYXc/tunisia)

---

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