# Nitrox Buddy vs Weights Check

The clearest difference is in-app purchases: Weights Check at none against Nitrox Buddy's 1. Weights Check also leads on update cadence (every 3 days vs every 7 months) and iOS requirement (17.0 vs 26.0). Nitrox Buddy's advantage is ratings volume (489 vs 1). On price, rating, ads and device support there is nothing between them.

Both are free to download. Nitrox Buddy sells 1 one-off in-app purchase. Weights Check asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 4.9 for Nitrox Buddy against 5.0 for Weights Check. That said, the two scores are not equally well evidenced: Nitrox Buddy has 489 ratings behind it against 1, so its average is the more settled of the two.

Nitrox Buddy ships an update every 7 months, Weights Check every 3 days. The most recent releases landed on October 17, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | Nitrox Buddy | Weights Check |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.9 (489 ratings)](https://appshunter.io/ios/app/nitrox-buddy/id572411073/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/weights-check-dive-weighting/id6806640499/reviews)** |
| Number of ratings | **489** | 1 |
| Positive reviews | 95.7% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 7 months | **Every 3 days** |
| Monetization | Free with in-app purchases | **Free** |
| Size | 6 MB | 9 MB |
| Requires iOS | 26.0 | **17.0** |
| Devices | **iPhone, Apple Watch** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Gereon Steffens](https://appshunter.io/developer/493030228) | [RUSTAM ISMAILOV](https://appshunter.io/developer/6799582362) |

## 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)


### Weights Check

[App page](https://appshunter.io/ios/app/weights-check-dive-weighting/id6806640499)

This app helps divers meticulously plan their lead requirements and buoyancy for dives. It allows users to build and save custom dive rigs with their own gear, then simulate and record actual dive conditions to refine future dives. It serves as a digital logbook for dive weighting and buoyancy, moving beyond memory to data-driven planning.

**Highlights:** Build custom dive rigs with personal gear, Simulate dive conditions and buoyancy, Record actual dive weighting and performance, Digital library of dive equipment, Visualize balance at stop and depth, Itemized rig breakdown

**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 Weights Check free?

Weights Check is free to download, with no in-app purchases.

### Which has better reviews, Nitrox Buddy or Weights Check?

Weights Check is rated higher. Nitrox Buddy averages 4.9 out of 5 from 489 ratings, while Weights Check averages 5.0 from 1 ratings.

### Do Nitrox Buddy or Weights Check have ads?

Neither Nitrox Buddy nor Weights Check shows ads.

### Which is updated more often, Nitrox Buddy or Weights Check?

Nitrox Buddy ships an update every 7 months, and Weights Check every 3 days. Most recently, Nitrox Buddy was updated on October 17, 2026 and Weights Check on October 8, 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.*