# Nitrox Helper vs Poseidon Reef

The clearest difference is in-app purchases: Poseidon Reef at none against Nitrox Helper's 4. Poseidon Reef also leads on update cadence (every 5 weeks vs every 9 months) and device support (4 vs 2). Nitrox Helper's advantage is ads (none vs shown). On price there is nothing between them.

Both are free to download. Nitrox Helper sells 4 in-app purchases, starting at $0.99 per month. Poseidon Reef asks for nothing beyond the download.

Nitrox Helper ships an update every 9 months, Poseidon Reef every 5 weeks. The most recent releases landed on November 2, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | Nitrox Helper | Poseidon Reef |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[3.0 (2 ratings)](https://appshunter.io/ios/app/poseidon-reef/id1581432645/reviews)** |
| Number of ratings | — | **2** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | Yes | **No** |
| Ads | **No** | Yes |
| Update frequency | Every 9 months | **Every 5 weeks** |
| Monetization | — | Ad-supported |
| Size | 7 MB | 58 MB |
| Requires iOS | 26.0 | **12.1** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [Robert O'Connell](https://appshunter.io/developer/1451300849) | [Poseidon Diving Systems AB](https://appshunter.io/developer/567839779) |

## What reviewers say

### Nitrox Helper

[App page](https://appshunter.io/ios/app/nitrox-helper/id1451300850)

**Features:** macOS Compatibility

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Monthly | $0.99 | per month |
| Pro 6 Monthly | $5.99 | per 6 months |
| Pro Annual | $9.99 | per year |
| Pro Lifetime | $49.99 | one-time |


### Poseidon Reef

[App page](https://appshunter.io/ios/app/poseidon-reef/id1581432645)

This app helps divers log, plan, and analyze their dives. It offers detailed overviews, customizable dive logs, and advanced planning for various dive types. Connect your dive computer to manage data and firmware.

**Highlights:** Comprehensive dive logging, Detailed dive planning, Support for OC and CCR dives, Unlimited tank support, Decompression model selection, Dive computer connectivity, Cloud backup and firmware updates

**In-app purchases:** none


## Frequently asked questions

### Is Nitrox Helper free?

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

### Is Poseidon Reef free?

Poseidon Reef is free to download, with no in-app purchases.

### Do Nitrox Helper or Poseidon Reef have ads?

Poseidon Reef shows ads; Nitrox Helper does not.

### Which is updated more often, Nitrox Helper or Poseidon Reef?

Nitrox Helper ships an update every 9 months, and Poseidon Reef every 5 weeks. Most recently, Nitrox Helper was updated on November 2, 2026 and Poseidon Reef on November 3, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*