# MQTT Spy vs YAML Tools

The clearest difference is rating: YAML Tools at 5.0 against MQTT Spy's 4.0. YAML Tools also leads on in-app purchases (none vs 1) and ads (none vs shown). MQTT Spy's advantage is price ($0.99 vs $3.99) and iOS requirement (10.0 vs 15.6). On ratings volume and device support there is nothing between them.

MQTT Spy costs $0.99 and YAML Tools $3.99 up front. MQTT Spy sells 1 one-off in-app purchase. YAML Tools asks for nothing beyond the download.

YAML Tools holds the better App Store score, 5.0 against 4.0. Both are backed by a comparable volume of ratings — 1 and 1 respectively.

MQTT Spy ships an update every 4 months, YAML Tools monthly. The most recent releases landed on November 7, 2026 and November 9, 2026 respectively.

## The numbers

| Metric | MQTT Spy | YAML Tools |
| --- | --- | --- |
| Price | **$0.99** | $3.99 |
| Rating | [4.0 (1 ratings)](https://appshunter.io/ios/app/mqtt-spy/id1564422794/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/yaml-tools/id6758571420/reviews)** |
| Number of ratings | 1 | 1 |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 4 months | **Monthly** |
| Monetization | **Free with in-app purchases** | Paid |
| Best chart rank | — | **#92** |
| Size | 26 MB | 30 MB |
| Requires iOS | **10.0** | 15.6 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Gopi Gadhiya](https://appshunter.io/developer/1387816354) | [Mohammed Aadhil](https://appshunter.io/developer/1526081218) |

## What reviewers say

### MQTT Spy

[App page](https://appshunter.io/ios/app/mqtt-spy/id1564422794)

This application allows for testing the pub/sub MQTT protocol. Connect to an MQTT broker to send and receive messages, control IoT devices, and monitor sensors. It offers features for saving broker lists, custom publishing buttons, and data monitoring in ASCII or HEX.

**Highlights:** Save broker list, Custom publish buttons, Monitor data as ASCII or HEX, Auto-send commands at intervals, Keep screen on/off option, Send log files

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $2.99 | one-time |


### YAML Tools

[App page](https://appshunter.io/ios/app/yaml-tools/id6758571420)

**Currently charting:** #92 Top Paid · Developer Tools (US App Store)

A comprehensive YAML utility for developers on iOS. Visualize, format, convert, and generate code from YAML files. Includes validation and a dedicated syntax keyboard for efficient editing.

**Highlights:** Interactive Tree and Table View for YAML visualization, Convert YAML to JSON, XML, CSV, and more, Generate type-safe model classes for multiple languages, Real-time JSON Schema generation and validation, Dedicated YAML syntax keyboard overlay, Format and minify YAML structures

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

**In-app purchases:** none


## Frequently asked questions

### Is MQTT Spy free?

MQTT Spy costs $0.99, and also offers in-app purchases.

### Is YAML Tools free?

YAML Tools costs $3.99, with no in-app purchases.

### Which has better reviews, MQTT Spy or YAML Tools?

YAML Tools is rated higher. MQTT Spy averages 4.0 out of 5 from 1 ratings, while YAML Tools averages 5.0 from 1 ratings.

### Do MQTT Spy or YAML Tools have ads?

MQTT Spy shows ads; YAML Tools does not.

### Which is updated more often, MQTT Spy or YAML Tools?

MQTT Spy ships an update every 4 months, and YAML Tools monthly. Most recently, MQTT Spy was updated on November 7, 2026 and YAML Tools on November 9, 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.*