# Master vs Attention Lab

The clearest difference is in-app purchases: Master at none against Attention Lab's 1. Attention Lab's advantage is update cadence (weekly vs fortnightly) and iOS requirement (14.0.0 vs 17.6). On price, ads and device support there is nothing between them.

Both are free to download. Attention Lab sells 1 one-off in-app purchase. Master asks for nothing beyond the download.

Master ships an update fortnightly, Attention Lab weekly. The most recent releases landed on October 31, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Master | Attention Lab |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/master-nav-colregs-iala-tests/id6758554000/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Fortnightly | **Weekly** |
| Monetization | Free | — |
| Size | 305 MB | 39 MB |
| Requires iOS | 17.6 | **14.0.0** |
| Devices | iPhone | **iPhone, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Peterjohn Chisholm](https://appshunter.io/developer/1602390398) | [KALLUM MARTIN](https://appshunter.io/developer/1896514205) |

## What reviewers say

### Master

[App page](https://appshunter.io/ios/app/master-nav-colregs-iala-tests/id6758554000)

Practice maritime navigation rules and buoyage systems with this app. It helps you identify knowledge gaps and track your progress in mastering essential regulations for mariners.

**Highlights:** USCG Navigation Rules practice, IALA Maritime Buoyage System tests, Knowledge gap identification, Progress tracking, Developed by Master Mariner

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

**In-app purchases:** none


### Attention Lab

[App page](https://appshunter.io/ios/app/attention-lab/id6767850515)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full Access | $0.99 | one-time |


## Frequently asked questions

### Is Master free?

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

### Is Attention Lab free?

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

### Do Master or Attention Lab have ads?

Neither Master nor Attention Lab shows ads.

### Which is updated more often, Master or Attention Lab?

Master ships an update fortnightly, and Attention Lab weekly. Most recently, Master was updated on October 31, 2026 and Attention Lab on October 25, 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.*