# Nitrox Buddy vs Gas Blender Toolkit

The clearest difference is price: Nitrox Buddy at Free against Gas Blender Toolkit's $2.99. Nitrox Buddy also leads on rating (4.9 vs 3.0) and review sentiment (96% vs 60%). Gas Blender Toolkit's advantage is in-app purchases (none vs 1) and update cadence (every 9 days vs every 7 months). On ads and device support there is nothing between them.

Nitrox Buddy is free to download; Gas Blender Toolkit costs $2.99 up front. Nitrox Buddy sells 1 one-off in-app purchase. Gas Blender Toolkit asks for nothing beyond the download.

Nitrox Buddy holds the better App Store score, 4.9 against 3.0. That said, the two scores are not equally well evidenced: Nitrox Buddy has 490 ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 96% of Nitrox Buddy's written reviews are positive against 60% of Gas Blender Toolkit's.

Nitrox Buddy ships an update every 7 months, Gas Blender Toolkit every 9 days. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Nitrox Buddy | Gas Blender Toolkit |
| --- | --- | --- |
| Price | **Free** | $2.99 |
| Rating | **[4.9 (490 ratings)](https://appshunter.io/ios/app/nitrox-buddy/id572411073/reviews)** | [3.0 (2 ratings)](https://appshunter.io/ios/app/gas-blender-toolkit/id1467768490/reviews) |
| Number of ratings | **490** | 2 |
| Positive reviews | **95.8% of reviews** | 60.0% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 7 months | **Every 9 days** |
| Monetization | **Free with in-app purchases** | Paid |
| Size | 6 MB | 3 MB |
| Requires iOS | 26.0 | **15.0** |
| Devices | iPhone, Apple Watch | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Gereon Steffens](https://appshunter.io/developer/493030228) | [Oleg Gurevich](https://appshunter.io/developer/1467768489) |

## What reviewers say

### Nitrox Buddy

[App page](https://appshunter.io/ios/app/nitrox-buddy/id572411073)

This application serves as a straightforward calculator for nitrox and enriched air divers. It quickly computes essential dive data such as Maximum Operating Depth (MOD), Equivalent Air Depth (EAD), Best Mix, and Partial Pressure of Oxygen (PPO2). It supports both imperial and metric units and offers a companion watch app for on-the-go calculations.

**Highlights:** Calculate MOD, EAD, Best Mix, PPO2, Imperial and metric unit support, Sea and fresh water options, Selectable max oxygen content, Selectable max partial pressure, Companion watch app

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Tip | $0.99 | one-time |

**What reviewers like**

- 👍 Easy to use
- 🚀 Quick calculations
- ✅ Accurate results
- 💡 Free to use
- 🎯 Essential for Nitrox divers

**What reviewers complain about**

- 📱 Ugly iPad icon
- ⚠️ MOD calculation limited to 40% O2 in older versions
- ⚠️ MOD calculation limited to 50% O2 in older versions
- ⚠️ Needs to work with older iOS versions

**Reported bugs**

- iPad icon is ugly
- MOD limit of 50% O2 despite 100% O2 setting (resolved)
- MOD limit of 40% O2 (older version)
- Does not work with older iOS versions

**Requested features**

- Add MOD 1.5 option
- Allow MOD calculation up to 100% O2 and indicate max exposure duration
- Change color for inappropriate mixes (e.g., 50% at 40m)
- Support older iOS versions (5 & 6)


### Gas Blender Toolkit

[App page](https://appshunter.io/ios/app/gas-blender-toolkit/id1467768490)

This comprehensive toolkit assists scuba divers in calculating and blending various gas mixtures like trimix, nitrox, and heliox. It offers features for both partial pressure and continuous blending, cost calculation, and utilizes ideal and real gas models for accuracy. Optimized for larger screens, it serves as a successor to a previous diving application.

**Highlights:** Partial pressure blending, Continuous blending, Trimix, nitrox, heliox calculations, Ideal and real gas models, Cost calculation, Top off from storage

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

**In-app purchases:** none


## Frequently asked questions

### Is Nitrox Buddy free?

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

### Is Gas Blender Toolkit free?

Gas Blender Toolkit costs $2.99, with no in-app purchases.

### Which has better reviews, Nitrox Buddy or Gas Blender Toolkit?

Nitrox Buddy is rated higher. Nitrox Buddy averages 4.9 out of 5 from 490 ratings, while Gas Blender Toolkit averages 3.0 from 2 ratings.

### Do Nitrox Buddy or Gas Blender Toolkit have ads?

Neither Nitrox Buddy nor Gas Blender Toolkit shows ads.

### Which is updated more often, Nitrox Buddy or Gas Blender Toolkit?

Nitrox Buddy ships an update every 7 months, and Gas Blender Toolkit every 9 days. Most recently, Nitrox Buddy was updated on October 24, 2026 and Gas Blender Toolkit 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.*