# OSTConf vs Halcyon Dive Systems

The clearest difference is update cadence: Halcyon Dive Systems at every 3 weeks against OSTConf's every 5 months. OSTConf's advantage is monetization model (free vs ad-supported) and device support (3 vs 1). On price, ads, in-app purchases and iOS requirement there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

OSTConf ships an update every 5 months, Halcyon Dive Systems every 3 weeks. The most recent releases landed on November 2, 2026 and November 4, 2026 respectively.

## The numbers

| Metric | OSTConf | Halcyon Dive Systems |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (8 ratings)](https://appshunter.io/ios/app/halcyon-dive-systems-diving/id6738069654/reviews)** |
| Number of ratings | — | **8** |
| Positive reviews | 25.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 3 weeks** |
| Monetization | **Free** | Ad-supported |
| Size | 3 MB | 162 MB |
| Requires iOS | 16.0 | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Kai-Uwe Sattler](https://appshunter.io/developer/500229044) | [Halcyon Dive Systems](https://appshunter.io/developer/1779189368) |

## What reviewers say

### OSTConf

[App page](https://appshunter.io/ios/app/ostconf/id1404182943)

Configure your dive computer settings and parameters wirelessly. Update date, time, custom text, gas mixes, and deco settings. Compatible with recent Bluetooth-enabled dive computers.

**Highlights:** Read and modify settings, Update date and time, Set custom text, Configure gas mixes, Set deco parameters, Upgrade firmware, Retrieve device information

**Features:** macOS Compatibility

**In-app purchases:** none


### Halcyon Dive Systems

[App page](https://appshunter.io/ios/app/halcyon-dive-systems-diving/id6738069654)

This app helps divers log, track, and share their underwater experiences. It offers integration with dive computers, personalized settings, and a community forum for connecting with other divers.

**Highlights:** Symbios integration for dive computer settings, Detailed dive logging and progress tracking, Social logbook for sharing dive stories, Connect with a global diving community, Personalized dive tips and advice, Exclusive benefits for Halcyon owners

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

**In-app purchases:** none


## Frequently asked questions

### Is OSTConf free?

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

### Is Halcyon Dive Systems free?

Halcyon Dive Systems is free to download, with no in-app purchases.

### Do OSTConf or Halcyon Dive Systems have ads?

Neither OSTConf nor Halcyon Dive Systems shows ads.

### Which is updated more often, OSTConf or Halcyon Dive Systems?

OSTConf ships an update every 5 months, and Halcyon Dive Systems every 3 weeks. Most recently, OSTConf was updated on November 2, 2026 and Halcyon Dive Systems on November 4, 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.*