Comparison

Subsurface vs Mares App

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

Head to head
About

Subsurface

This application allows divers to manage their dive logs on their mobile devices. It supports editing dive data and downloading new information from compatible dive computers. Optional cloud synchronization is available for seamless data transfer with desktop versions.

Highlights
  • Mobile dive log management
  • Edit dive data
  • Download from Bluetooth LE dive computers
  • Optional cloud synchronization
  • Open-source and free
Read full description

Subsurface-mobile is an iOS dive log application based on Subsurface, the best free open source dive log application available on Windows, Mac and Linux. Subsurface-mobile allows you to access your dive log on your tablet or phone, edit the data and even download new dive information from many Bluetooth LE enabled dive computers. Using a free Subsurface Cloud Storage account you can synchronize your dive data with the Subsurface desktop application (while significantly increasing the usefulness, the cloud account is not required to use Subsurface-mobile). To get support from the developers, please use the in-app menu entry "Ask for support" Please check out the Subsurface-mobile user manual: https://subsurface-divelog.org/documentation/subsurface-mobile-v3-user-manual (also available from within the app) Subsurface-mobile is free and open source. No ads, no commercial anything. And it comes with free cloud storage (if you decide to use that - it's optional). Your data aren't used for anything, nothing gets monetized.

About

Mares App

Transform your Apple Watch Ultra into a dive computer, recording dives directly on your wrist. Log scuba, freediving, and technical dives, manage dive sites, and track underwater wildlife sightings. Share your adventures with dive buddies and keep your equipment details organized.

Highlights
  • Apple Watch Ultra dive computer integration
  • Digital dive logbook
  • Dive site database and management
  • Underwater wildlife tracking
  • Dive buddy sharing
  • Dive equipment management
  • Firmware updates
Features
Read full description

APPLE WATCH ULTRA DIVE COMPUTER Transform your Ultra into a dive computer. Record dives directly on your wrist and sync automatically to the Mares App. (In-app purchase required.) DIGITAL LOGBOOK: Log your Scuba, Freediving, Extended Range and Rebreather (SCR/CCR) dives in seconds via Bluetooth. Easily share your dives via QR code. Add new dives with your device’s GPS and download your dives from selected dive computers (1*). DIVE SITES: With the help of the Mares dive site database, you can immediately assign a dive site to your logged dives. You can also add your own private dive sites and share them with your dive buddies using a QR code. You can download your dive data directly from selected Mares dive computers . WILDLIFE: A variety of local wildlife is already stored in the app for individual dive sites. This means you can immediately assign the highlights of your underwater encounters to your logged dives. Your sightings are displayed on your personal world map. DIVE BUDDIES: Easily add your dive buddies via QR code or manually in the app. Share your best dives and most exciting animal encounters with friends using the Mares app. STATISTICS: All your dives and data can be seen at a glance, including your longest or deepest dive, your average dive time and more! DIGITAL EQUIPMENT: Store important dive equipment details, including serial numbers, photos and invoices. Enter maintenance dates and keep track of when your equipment needs to be serviced. NEWS AND VIDEOS: Stay up-to-date with all the latest news and videos from the world of water sports and diving. FIRMWARE: When you connect your dive computer to the app, you will be able to confirm if you have the latest firmware. As soon as it is outdated, you will receive a message regarding the newest firmware to download. TABLES: Here you will find useful information such as decompression tables and emergency scenarios. 1* Currently available for MARES Sirius, Sirius L, Sirius Hunter, Horizon, Genius, Quad CI, Quad 2, Quad Air, Quad, Puck 4, Puck Pro EZ, Puck lite, Puck Pro, Puck Pro Plus, Puck Air 2, Smart, Smart Apnea, Smart Air Terms of Use (EULA) Mares App for Apple Watch Ultra: https://my.divessi.com/published/viewhls/awu_terms_v1/2

Screenshots

Subsurface4 screens
Mares App4 screens

Verdict

The call

The clearest difference is in-app purchases: Subsurface at none against Mares App's 8. Subsurface also leads on review sentiment (63% vs 47%). Mares App's advantage is update cadence (every 3 weeks vs every 2 months) and ratings volume (183 vs 48). On price, rating, ads and device support 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. Mares App sells 8 in-app purchases, starting at $2.99 per month. Subsurface asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.5 for Subsurface against 4.5 for Mares App. Both are backed by a comparable volume of ratings — 48 and 183 respectively. Written reviews are what separate them: 63% of Subsurface's written reviews are positive against 47% of Mares App's.

UpkeepUpdate frequency

Subsurface ships an update every 2 months, Mares App every 3 weeks. The most recent releases landed on September 18, 2026 and September 26, 2026 respectively.

Scorecard5 real differences · 5 level
Subsurface versus Mares App: the parameters behind the verdict, then further details
ParameterSubsurfaceMares App
PriceFreeFree
Rating4.5 (48 ratings)4.5 (183 ratings)
Positive reviews63.3% of reviews — better47.5% of reviews
Number of ratings48183 — better
Update frequencyEvery 2 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPadiPhone, iPad, Apple Watch — better
Requires iOS1716.6 — better
Further details — not scored
Size52 MB247 MB
Age rating4+4+
DeveloperDirk HohndelHead Watersports S.p.A.

Customer experience

Subsurface

All ratings48 ratings
Positive89.6%
Neutral2.1%
Negative8.3%
Written reviews30 reviews
Positive63.3%
Neutral6.7%
Negative30.0%

Mares App

All ratings183 ratings
Positive89.6%
Neutral4.9%
Negative5.5%
Written reviews99 reviews
Positive47.5%
Neutral12.1%
Negative40.4%

In-app purchases

None

Subsurface

No in-app purchases

8 purchases

Mares App

Subscriptions8
  • Snorkel Only$2.991 Month
  • Full Featured Month (Housing Only)3 Days trial$6.991 Month
  • Full Featured Month (Ultra Only)3 Days trial$6.991 Month
Show 5 more
  • MARES Fully Featured Monthly3 Days trial$8.991 Month
  • Full Featured Yearly (Housing Only)3 Days trial$49.991 Year
  • Full Featured Yearly (Ultra Only)3 Days trial$49.991 Year
  • MARES Fully Featured Yearly3 Days trial$69.991 Year
  • MARES Fully Featured Yearly Family3 Days trial$119.991 Year

Questions

Is Subsurface free?
Subsurface is free to download, with no in-app purchases.
Is Mares App free?
Mares App is free to download, with in-app purchases available.
Which has better reviews, Subsurface or Mares App?
Subsurface and Mares App are both rated 4.5 out of 5 on the App Store, from 48 and 183 ratings respectively.
Do Subsurface or Mares App have ads?
Neither Subsurface nor Mares App shows ads.
Which is updated more often, Subsurface or Mares App?
Subsurface ships an update every 2 months, and Mares App every 3 weeks. Most recently, Subsurface was updated on September 18, 2026 and Mares App on September 26, 2026.

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