# Nitrox Tools vs Halcyon Dive Systems

The clearest difference is price: Halcyon Dive Systems at Free against Nitrox Tools's $5.99. Halcyon Dive Systems also leads on update cadence (every 2 weeks vs every 5 months). Nitrox Tools's advantage is device support (4 vs 1). On rating, ratings volume, ads and in-app purchases there is nothing between them.

Halcyon Dive Systems is free to download; Nitrox Tools costs $5.99 up front. Neither carries in-app purchases, so what you see is what you pay.

On the App Store both sit at effectively the same score — 5.0 for Nitrox Tools against 5.0 for Halcyon Dive Systems. Both are backed by a comparable volume of ratings — 4 and 8 respectively.

Nitrox Tools ships an update every 5 months, Halcyon Dive Systems every 2 weeks. The most recent releases landed on September 23, 2026 and July 24, 2026 respectively.

## The numbers

| Metric | Nitrox Tools | Halcyon Dive Systems |
| --- | --- | --- |
| Price | $5.99 | **Free** |
| Rating | [5.0 (4 ratings)](https://appshunter.io/ios/app/nitrox-tools/id284919980/reviews) | [5.0 (8 ratings)](https://appshunter.io/ios/app/halcyon-dive-systems-diving/id6738069654/reviews) |
| Number of ratings | 4 | **8** |
| Positive reviews | 88.5% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 2 weeks** |
| Monetization | Paid | **Ad-supported** |
| Size | 7 MB | 159 MB |
| Requires iOS | **15.6** | 16.0 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Greg Mclaughlin](https://appshunter.io/developer/284919983) | [Halcyon Dive Systems](https://appshunter.io/developer/1779189368) |

## What reviewers say

### Nitrox Tools

[App page](https://appshunter.io/ios/app/nitrox-tools/id284919980)

This app provides essential tools for divers to plan and blend enriched air nitrox. It calculates dive parameters like equivalent air depth and maximum operating depth, and supports various blending methods for custom gas mixes. Easily switch between metric and imperial units and save custom settings for frequent use.

**Highlights:** Enriched air nitrox blending, Dive planning calculations, Equivalent Air Depth (EAD), Partial Pressure of Oxygen (PPO2), Maximum Operating Depth (MOD), Save custom mixes and settings, Metric/Imperial unit switching

**Features:** Vision Pro support

**In-app purchases:** none


### Halcyon Dive Systems

[App page](https://appshunter.io/ios/app/halcyon-dive-systems-diving/id6738069654)

This app helps divers log, track, and share their underwater experiences. It offers integration with dive computers, personalized settings, and a community forum for connecting with other divers.

**Highlights:** Symbios integration for dive computer settings, Detailed dive logging and progress tracking, Social logbook for sharing dive stories, Connect with a global diving community, Personalized dive tips and advice, Exclusive benefits for Halcyon owners

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

**In-app purchases:** none


## Frequently asked questions

### Is Nitrox Tools free?

Nitrox Tools costs $5.99, with no in-app purchases.

### Is Halcyon Dive Systems free?

Halcyon Dive Systems is free to download, with no in-app purchases.

### Which has better reviews, Nitrox Tools or Halcyon Dive Systems?

Nitrox Tools and Halcyon Dive Systems are both rated 5.0 out of 5 on the App Store, from 4 and 8 ratings respectively.

### Do Nitrox Tools or Halcyon Dive Systems have ads?

Neither Nitrox Tools nor Halcyon Dive Systems shows ads.

### Which is updated more often, Nitrox Tools or Halcyon Dive Systems?

Nitrox Tools ships an update every 5 months, and Halcyon Dive Systems every 2 weeks. Most recently, Nitrox Tools was updated on September 23, 2026 and Halcyon Dive Systems on July 24, 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.*