Adam’s Deepblu Cosmiq+ App is free and runs in your browser. It needs no installation, no account and no cable.
If you still dive with a Deepblu Cosmiq+, this one is for you. I built a free web app that talks to your watch over Bluetooth. You can adjust its settings, download your dive log, write notes on every dive, and back it all up to your own Google Drive. You can also install it on your phone like a normal app and use it offline.
👉 Open the app: https://cosmiq.garfield.in/
The app connected to a Cosmiq+: model, firmware and settings at a glance.
Why I built it
A dive computer should keep working for as long as you keep diving. Your watch is still fine, so you should still be able to set it up, read your dives and keep a proper logbook. This app is my answer: one page that works on a phone, tablet or laptop, with a clean, dark design that is easy to read next to the water.
What the app does
1. Manage your watch settings
Everything you would want to change is organised into four tabs:
- General: default mode (scuba, freedive or gauge), sync the watch clock to your phone, metric or imperial units, date display, screen timeout, backlight and eco mode.
- Environment: fresh or salt water, safety factor and air/nitrox mix.
- Scuba: PPO2 limit and depth alarms.
- Freedive: dive-time and depth alarms.
After each change the app tells you if the watch accepted it, so you are never left guessing.
2. Download and browse your logbook
Tap one button and the app reads your dives off the watch. You get totals (number of dives, deepest dive, total time under water) and a card for every dive with date, gas, maximum depth, duration and minimum temperature, plus a small depth sparkline.
Tap any dive to open its detail view: the full depth and temperature profile, average depth and sample count. You can flick through your dives with the Newer and Older buttons.
3. Keep your own dive notes
Add the dive site, notes and a star rating to each dive. Where was it, what did you see, how was the visibility? Those details are what make a logbook worth reading years later.
4. Sync to your own Google Drive (optional)
Connect your Google account and the app saves your logbook and notes into a folder called “Adam’s Cosmiq+ App” in your Drive. Use auto-sync to back up after every download, or tap Sync now whenever you like.
Syncing also keeps your devices in step. Download dives on your phone in the morning, open the app on your laptop in the evening, and everything is there. Dives from several devices are merged, never overwritten.
5. Export to other tools
Export your logbook as Subsurface XML, CSV or raw JSON, and optionally upload the XML and CSV to your Drive.
6. Install it on your phone and use it offline
If you use Google Chrome on your Android phone, you can install the app as a proper in-app shortcut. Once it’s installed, it opens full screen from your home screen and keeps working even when you have no signal. That’s handy on a boat or at a remote dive site.
Your privacy comes first
There is no server and no account with me. Your dive data stays in your browser. If you choose Drive sync, it is saved in your own Google Drive, and the app only asks for Google’s narrowest permission (drive.file). That means it can see only the files it created and can’t open anything else in your Drive. I don’t collect analytics and I don’t sell or share data. You can read the details in the Privacy Policy and Terms of Service.
Quick-start tutorial
What you need
- A Deepblu Cosmiq+ with Bluetooth turned on.
- Android or a computer: Google Chrome or Microsoft Edge.
- iPhone or iPad: the free Bluefy browser from the App Store. Safari doesn’t support Web Bluetooth.
Step 1: Open the app
Go to https://cosmiq.garfield.in/ in Chrome.
Step 2: Install it (optional, but recommended)
On Chrome for Android, tap the ⋮ menu and choose Install app (or Add to Home screen). Confirm, and the app appears on your home screen with its own icon. From now on it opens full screen and works offline. On a computer, click the install icon in the address bar.
Step 3: Connect your watch
Wake up your Cosmiq+ and keep it close to your phone. Tap Connect, choose your watch from the Bluetooth list and wait a few seconds. The status chip turns to Connected, and the app shows your model, firmware version and current settings.
Step 4: Change a setting
Open the Settings tab, pick a sub-tab and change what you need. A small message confirms each change. Settings stay locked until a watch is connected, which protects you from accidental taps.
Step 5: Download your dives
Open the Logbook tab and tap Download dives from Cosmiq+. Keep the watch near your phone and the screen on until it finishes. The first download with a full memory takes the longest. After that, tap any dive to see its profile.
Step 6: Add notes
In a dive’s detail view, fill in the dive site, your notes and a rating, then tap Save dive notes.
Step 7: Back up to Drive
Open the Cloud tab, tap Connect Google Drive and sign in with your Google account. Leave auto-sync on, and your logbook is backed up after every download. To use another phone or laptop, open the app there, connect the same Google account and tap Sync now.
Step 8: Export (optional)
On the Logbook tab, tap Subsurface XML or CSV to save a copy for other dive-log software.
Tips and troubleshooting
- The watch doesn’t show up in the Bluetooth list. Wake the watch, make sure Bluetooth is on, and make sure no other app is already connected to it.
- A setting says it was rejected. Reconnect and try again. If it keeps happening, tell me your model and firmware.
- Downloading is slow. That’s normal with a full memory. Keep the watch close and the screen awake.
- Sync asks me to sign in again. Google sign-in sessions last about an hour. Reconnect from the Cloud tab and continue.
- I’m on iPhone. Use the Bluefy browser, because Safari can’t talk to Bluetooth devices.
Please read: safety first
This is independent, unofficial software. It is not made or endorsed by Deepblu, and it works by reverse-engineering how the watch communicates. Some settings, like safety factor and gas mix, change how your watch calculates decompression. Always check every setting on the watch itself before you dive, and always carry a backup. Neither the app nor I accept responsibility for malfunction or incorrect settings.
Credits and thanks
The Bluetooth protocol and logbook-reading work builds on the open-source cosmiq5-web project (MIT licence). A big thank-you to its authors for making this possible.
Tell me how it goes
This app grows with your feedback. If you try it, I’d like to hear which Cosmiq model and firmware you have and what worked or didn’t. Leave a comment below, or share the app with a dive buddy who still wears a Cosmiq+.
Dive safe, and enjoy the logbook! 🤿