# MUST PROFESSOR vs GMDSS TRAINER

The clearest difference is in-app purchases: MUST PROFESSOR at none against GMDSS TRAINER's 1. MUST PROFESSOR also leads on iOS requirement (15.6 vs 26.1). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. GMDSS TRAINER sells 1 one-off in-app purchase. MUST PROFESSOR asks for nothing beyond the download.

MUST PROFESSOR ships an update monthly, GMDSS TRAINER every 4 weeks. The most recent releases landed on November 3, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | MUST PROFESSOR | GMDSS TRAINER |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (2 ratings)](https://appshunter.io/ios/app/gmdss-trainer/id6757383433/reviews)** |
| Number of ratings | — | **2** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Monthly | **Every 4 weeks** |
| Monetization | — | Free |
| Size | 24 MB | 27 MB |
| Requires iOS | **15.6** | 26.1 |
| Devices | iPhone, iPod | **iPhone, iPad, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [batjargal chuluunkhuu](https://appshunter.io/developer/1538719237) | [Osprey Applications LLC](https://appshunter.io/developer/1619576372) |

## What reviewers say

### MUST PROFESSOR

[App page](https://appshunter.io/ios/app/must-professor/id1556175407)

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

**In-app purchases:** none


### GMDSS TRAINER

[App page](https://appshunter.io/ios/app/gmdss-trainer/id6757383433)

Prepare for FCC maritime radio operator exams with this comprehensive study companion. It features official question pools, AI-powered explanations for complex topics, and flexible study modes to help you understand material and pass your certification tests.

**Highlights:** Official FCC question pools, AI-powered explanations, Multiple study modes (Practice, Exam, Review), Detailed analytics and progress tracking, Smart flagging for difficult questions, Topic-based performance breakdowns

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full Access | $14.99 | one-time |


## Frequently asked questions

### Is MUST PROFESSOR free?

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

### Is GMDSS TRAINER free?

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

### Do MUST PROFESSOR or GMDSS TRAINER have ads?

Neither MUST PROFESSOR nor GMDSS TRAINER shows ads.

### Which is updated more often, MUST PROFESSOR or GMDSS TRAINER?

MUST PROFESSOR ships an update monthly, and GMDSS TRAINER every 4 weeks. Most recently, MUST PROFESSOR was updated on November 3, 2026 and GMDSS TRAINER on October 31, 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.*