# Master vs IRPCS

The clearest difference is price: IRPCS at Free against Master's $0.99. IRPCS also leads on update cadence (every 3 days vs every 3 months) and iOS requirement (15.1 vs 17.6). Master's advantage is in-app purchases (none vs 2) and ads (none vs shown). On device support there is nothing between them.

IRPCS is free to download; Master costs $0.99 up front. IRPCS sells 2 in-app purchases, starting at $4.99 per month. Master asks for nothing beyond the download.

Master ships an update every 3 months, IRPCS every 3 days. Both last shipped on November 5, 2026.

## The numbers

| Metric | Master | IRPCS |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/master-nav-iala-mbs/id6757947717/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 3 months | **Every 3 days** |
| Monetization | Paid | — |
| Size | 219 MB | 73 MB |
| Requires iOS | 17.6 | **15.1** |
| Devices | iPhone | **iPhone, iPod** |
| Age rating | 4+ | 17+ |
| Developer | [Peterjohn Chisholm](https://appshunter.io/developer/1602390398) | [Paul Whittle](https://appshunter.io/developer/1076749256) |

## What reviewers say

### Master

[App page](https://appshunter.io/ios/app/master-nav-iala-mbs/id6757947717)

This app simplifies learning the IALA Maritime Buoyage System through interactive visuals and exam-style practice. It helps users quickly identify and explain maritime marks, building a comprehensive understanding for maritime qualifications.

**Highlights:** Interactive visuals, Memory aids, Exam-ready answer phrases, Step-by-step learning, Exam-style practice, Recognition training, Chart symbol teaching

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

**In-app purchases:** none


### IRPCS

[App page](https://appshunter.io/ios/app/irpcs/id6762519800)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| IRPCS Pro 1 month | $4.99 | per month |
| IRPCS Pro | $29.99 | per year |


## Frequently asked questions

### Is Master free?

Master costs $0.99, with no in-app purchases.

### Is IRPCS free?

IRPCS is free to download, with in-app purchases available.

### Do Master or IRPCS have ads?

IRPCS shows ads; Master does not.

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

Master ships an update every 3 months, and IRPCS every 3 days. Most recently, Master was updated on November 5, 2026 and IRPCS on November 5, 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.*