Poseidon Reef vs Halcyon Dive Systems
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Poseidon Reef
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.
- 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
Read full descriptionHide full description
Dive into the deep with Reef, the ultimate tool for every diver regardless of experience, level, or dive style. Designed to enhance and prolong your passion for diving, Reef seamlessly extends your diving experience, both before and after the actual dive. With Reef in your pocket, you're always ready to explore. Dive Log > Get a comprehensive and detailed overview of all your dives. > Easily sort and filter to find specific dives. > Import and export dives effortlessly. > Personalize dives with custom details, photos, location and more. > Engage with your dives using the interactive chart functionality. > Visualize intricate data like tank pressures, pO2, loop temperature, etc.* > Choose the data points you want to see > Zoom in on portions of the dive you are interested in Planner > Keep track of all your upcoming dives with a comprehensive overview. > Sort, filter, and organize your dive plans. > Plan for a single dive or a series of dives. > Suitable for OC (Open Circuit) and CCR (Closed Circuit Rebreather) dives. > Supports an unlimited number of tanks. > Choose between DCAP and Buhlmann decompression models. > Bailout scenario > Configure gas content Device Manager > Connect your Poseidon M28 dive computer through WiFi > View details about connected submodules. > Download, store, and back up your dives in the cloud. > Access vital service information > Monitor total dive time > Stay updated with firmware information. *Only available with Poseidon M28 dive computer
Halcyon Dive Systems
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.
- 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
Read full descriptionHide full description
Explore without limits: Your Ultimate Diving App Dive smarter and safer with the Halcyon App. Enjoy this powerful tool for logging, tracking, and sharing all your diving experiences while experiencing unprecedented integration with your Halcyon computer. With the Haclyon app you have full control over all computer settings, allowing the creation of profiles that include tailored settings and gases, pushed to the computer with the click of a button. You can also enjoy a full-featured "dry-diving" mode to explore all the unique features of our Symbios-connected products. From beginners to seasoned pros, the Halcyon App empowers you to explore the underwater world with confidence, share with our vibrant community, and track your diving progress. Key Features: Symbios Integration: Sync with Symbios-enabled devices, including the Handset, HUD, Rebreather and more. Manage your settings, create saved profiles with tailored settings and gases, track dive profiles, and access advanced metrics. Log Your Dives: Keep a detailed record of your dives. Monitor your progress over time and relive your diving adventures. Social Logbook: Share your dive stories, photos, and achievements with divers worldwide. Stay motivated and inspire others along the way. Diving Community: Connect with divers at any level. Share tips, discover new dive spots, and stay in the loop with the latest dive trends. Personalized Dive Tips: Get advice tailored to your diving experience with helpful tips and tricks, no matter your skill level. Halcyon Owner Benefits: Enjoy exclusive perks if you're a Halcyon owner—priority support, extended warranties, and special offers to get the most out of your gear. Why Choose Halcyon App? The Halcyon App isn’t just for logging and tracking—it’s your gateway to a richer diving experience. With cutting-edge technology, a thriving community, and personalized insights, the Halcyon App helps you dive smarter, stay connected, and explore like never before. Whether you're diving at a technical site or simply enjoying a recreational dive, the app ensures every dive is memorable, safe, and exciting. Stay Connected, Stay Inspired Join a passionate diving community where you can share experiences, connect with fellow divers, and keep up with the latest Halcyon innovations. The Future of Diving Is Here With Symbios Ecosystem integration, the Halcyon App lets you customize and track your gear, log dives, and connect with divers worldwide. Experience the underwater world with the latest tools, all from your phone. For Divers at Every Stage Whether you're just starting out or have hundreds of dives under your belt, the Halcyon App helps you track your dives, manage your gear, and stay in touch with the diving community. Download Halcyon App Today Join the next generation of divers—download Halcyon App and start exploring without limits.
Screenshots
Verdict
The clearest difference is rating: Halcyon Dive Systems at 5.0 against Poseidon Reef's 3.0. Halcyon Dive Systems also leads on ads (none vs shown) and ratings volume (8 vs 2). Poseidon Reef's advantage is device support (4 vs 1) and iOS requirement (12.1 vs 16.0). On price, update cadence, in-app purchases and monetization model there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
Halcyon Dive Systems holds the better App Store score, 5.0 against 3.0. Both are backed by a comparable volume of ratings — 2 and 8 respectively.
Poseidon Reef ships an update every 5 weeks, Halcyon Dive Systems every 3 weeks. The most recent releases landed on November 3, 2026 and November 4, 2026 respectively.
| Parameter | Poseidon Reef | Halcyon Dive Systems |
|---|---|---|
| Price | Free | Free |
| Rating | 3.0 (2 ratings) | 5.0 (8 ratings) — better |
| Positive reviews | 0.0% of reviews | — |
| Number of ratings | 2 | 8 — better |
| Update frequency | Every 5 weeks | Every 3 weeks — better |
| Ads | Yes | No — better |
| In-app purchases | No | No |
| Monetization | Ad-supported | Ad-supported |
| Devices | iPhone, iPad, iPod, Mac — better | iPhone |
| Requires iOS | 12.1 — better | 16.0 |
| Further details — not scored | ||
| Size | 58 MB | 162 MB |
| Age rating | 4+ | 4+ |
| Developer | Poseidon Diving Systems AB | Halcyon Dive Systems |
Customer experience
Poseidon Reef
Halcyon Dive Systems
In-app purchases
Poseidon Reef
No in-app purchases
Halcyon Dive Systems
No in-app purchases
Questions
Is Poseidon Reef free?
Is Halcyon Dive Systems free?
Which has better reviews, Poseidon Reef or Halcyon Dive Systems?
Do Poseidon Reef or Halcyon Dive Systems have ads?
Which is updated more often, Poseidon Reef or Halcyon Dive Systems?
Other comparisons















