Comparison

Poseidon Reef vs Depth.

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

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.

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
Read 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

About

Depth.

Features
Read full description

Depth. is your dive log for iPhone. Simple, fast and beautiful. LOG EVERY DIVE Location, depth, dive time, water temperature, visibility, equipment, weights and buddy all in one place. Dives are automatically saved to your account. MARINE SPECIES Save species you encounter during your dive. Depth. has an extensive catalog with photos and information about fish, coral and other underwater animals. BUDDY SYSTEM Send a dive directly to your buddy via their Depth ID. They will see your log appear in their timeline. AI ASSISTANT Ask questions about diving techniques, species or your equipment. The built-in AI assistant will help you further. EXPORT Download all your dives as JSON, CSV or XML compatible with other logbooks. IMPORT Do you dive via Diviac? Import all your existing dives with one tap. DESIGNED FOR DIVERS No subscriptions. No ads. Just a clean, quick logbook that you always have with you.

Screenshots

Poseidon Reef4 screens
Depth.4 screens

Verdict

The call

The clearest difference is ads: Depth. at none against Poseidon Reef's shown. Poseidon Reef's advantage is device support (4 vs 2) and iOS requirement (12.1 vs 16.0). On price, update cadence and in-app purchases 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

CostPrice · In-app purchases · Ads · Monetization

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

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 5 weeks. The most recent releases landed on October 16, 2026 and October 24, 2026 respectively.

Scorecard3 real differences · 7 level
Poseidon Reef versus Depth.: the parameters behind the verdict, then further details
ParameterPoseidon ReefDepth.
PriceFreeFree
Rating3.0 (2 ratings) — better—
Positive reviews0.0% of reviews—
Number of ratings2 — better—
Update frequencyEvery 5 weeksEvery 5 weeks
AdsYesNo — better
In-app purchasesNoNo
MonetizationAd-supported—
DevicesiPhone, iPad, iPod, Mac — betteriPhone, iPad
Requires iOS12.1 — better16.0
Further details — not scored
Size58 MB2 MB
Age rating4+4+
DeveloperPoseidon Diving Systems ABJosephus Fransiscus Zegers

In-app purchases

None

Poseidon Reef

No in-app purchases

None

Depth.

No in-app purchases

Questions

Is Poseidon Reef free?
Poseidon Reef is free to download, with no in-app purchases.
Is Depth. free?
Depth. is free to download, with no in-app purchases.
Do Poseidon Reef or Depth. have ads?
Poseidon Reef shows ads; Depth. does not.
Which is updated more often, Poseidon Reef or Depth.?
Poseidon Reef ships an update every 5 weeks, and Depth. every 5 weeks. Most recently, Poseidon Reef was updated on October 16, 2026 and Depth. on October 24, 2026.

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