# Nitrox Buddy vs Thalos

The clearest difference is monetization model: Nitrox Buddy at free with in-app purchases against Thalos's subscription. Nitrox Buddy also leads on ratings volume (468 vs 2). Thalos's advantage is update cadence (daily vs every 7 months) and iOS requirement (15.1 vs 26.0). On price, rating, ads and in-app purchases there is nothing between them.

Both are free to download. Nitrox Buddy sells 1 one-off in-app purchase and Thalos sells 2 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

On the App Store both sit at effectively the same score — 4.9 for Nitrox Buddy against 5.0 for Thalos. That said, the two scores are not equally well evidenced: Nitrox Buddy has 468 ratings behind it against 2, so its average is the more settled of the two.

Nitrox Buddy ships an update every 7 months, Thalos daily. The most recent releases landed on October 14, 2026 and October 13, 2026 respectively.

## The numbers

| Metric | Nitrox Buddy | Thalos |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.9 (468 ratings)](https://appshunter.io/ios/app/nitrox-buddy/id572411073/reviews) | **[5.0 (2 ratings)](https://appshunter.io/ios/app/thalos/id6761337227/reviews)** |
| Number of ratings | **468** | 2 |
| Positive reviews | 95.7% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 7 months | **Daily** |
| Monetization | **Free with in-app purchases** | Subscription |
| Size | 6 MB | 41 MB |
| Requires iOS | 26.0 | **15.1** |
| Devices | **iPhone, iPod, Apple Watch** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Gereon Steffens](https://appshunter.io/developer/493030228) | [JOHN WALLIS YOUNGBLOOD](https://appshunter.io/developer/1888980268) |

## 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

**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)


### Thalos

[App page](https://appshunter.io/ios/app/thalos/id6761337227)

This comprehensive dive app offers a robust dive logbook, detailed dive site information with emergency plans, and multiple dive calculators. It includes features for instructors to manage students and courses, and a social feed for divers to connect and share experiences. The app works fully offline, ensuring critical data is always accessible.

**Highlights:** Offline dive logbook, Dive site database with emergency plans, 9 essential dive calculators, Instructor module for course management, Social feed and community features, Emergency mode for critical access

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Thalos | $2.99 | per month |
| Thalos | $19.99 | per year |


## Frequently asked questions

### Is Nitrox Buddy free?

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

### Is Thalos free?

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

### Which has better reviews, Nitrox Buddy or Thalos?

Thalos is rated higher. Nitrox Buddy averages 4.9 out of 5 from 468 ratings, while Thalos averages 5.0 from 2 ratings.

### Do Nitrox Buddy or Thalos have ads?

Neither Nitrox Buddy nor Thalos shows ads.

### Which is updated more often, Nitrox Buddy or Thalos?

Nitrox Buddy ships an update every 7 months, and Thalos daily. Most recently, Nitrox Buddy was updated on October 14, 2026 and Thalos on October 13, 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.*