# Nitrox Buddy vs Mares App

The clearest difference is review sentiment: Nitrox Buddy at 96% against Mares App's 47%. Nitrox Buddy also leads on rating (4.9 vs 4.5). Mares App's advantage is update cadence (every 3 weeks vs every 7 months) and iOS requirement (16.6 vs 26.0). On price, ratings volume, 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 Mares App sells 8 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

Nitrox Buddy holds the better App Store score, 4.9 against 4.5. Both are backed by a comparable volume of ratings — 468 and 183 respectively. Written reviews point the same way: 96% of Nitrox Buddy's written reviews are positive against 47% of Mares App's.

Nitrox Buddy ships an update every 7 months, Mares App every 3 weeks. Both last shipped on September 21, 2026.

## The numbers

| Metric | Nitrox Buddy | Mares App |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.9 (468 ratings)](https://appshunter.io/ios/app/nitrox-buddy/id572411073/reviews)** | [4.5 (183 ratings)](https://appshunter.io/ios/app/mares-app/id1625641063/reviews) |
| Number of ratings | **468** | 183 |
| Positive reviews | **95.7% of reviews** | 47.5% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 7 months | **Every 3 weeks** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 6 MB | 247 MB |
| Requires iOS | 26.0 | **16.6** |
| Devices | iPhone, iPod, Apple Watch | iPhone, iPad, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [Gereon Steffens](https://appshunter.io/developer/493030228) | [Head Watersports S.p.A.](https://appshunter.io/developer/1193522423) |

## 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)


### Mares App

[App page](https://appshunter.io/ios/app/mares-app/id1625641063)

Transform your Apple Watch Ultra into a dive computer, recording dives directly on your wrist. Log scuba, freediving, and technical dives, manage dive sites, and track underwater wildlife sightings. Share your adventures with dive buddies and keep your equipment details organized.

**Highlights:** Apple Watch Ultra dive computer integration, Digital dive logbook, Dive site database and management, Underwater wildlife tracking, Dive buddy sharing, Dive equipment management, Firmware updates

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

**In-app purchases (8)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Snorkel Only | $2.99 | per month |
| Full Featured Month (Housing Only) | $6.99 | per month |
| Full Featured Month (Ultra Only) | $6.99 | per month |
| MARES Fully Featured Monthly | $8.99 | per month |
| Full Featured Yearly (Housing Only) | $49.99 | per year |
| Full Featured Yearly (Ultra Only) | $49.99 | per year |
| MARES Fully Featured Yearly | $69.99 | per year |
| MARES Fully Featured Yearly Family | $119.99 | per year |


## Frequently asked questions

### Is Nitrox Buddy free?

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

### Is Mares App free?

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

### Which has better reviews, Nitrox Buddy or Mares App?

Nitrox Buddy is rated higher. Nitrox Buddy averages 4.9 out of 5 from 468 ratings, while Mares App averages 4.5 from 183 ratings.

### Do Nitrox Buddy or Mares App have ads?

Neither Nitrox Buddy nor Mares App shows ads.

### Which is updated more often, Nitrox Buddy or Mares App?

Nitrox Buddy ships an update every 7 months, and Mares App every 3 weeks. Most recently, Nitrox Buddy was updated on September 21, 2026 and Mares App on September 21, 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.*