Atmos Mission One: Freediving Watch Review
The Atmos Mission One in action during a freediving session.

Atmos Mission One: Freediving Watch Review


  • 10 sets of both depth alarms and time alarms
  • Deep freediving surface interval alarm for nitrogen off-gasing
  • Noise and vibration alarms are customizable
  • Logbook shows depth profile and other diving info
  • Connects to mobile app to visualize diving data

In this article we will specifically look at the details that make the Atmos Mission One a great choice as a freediving watch.

We tried and tested the watch as a depth training tool specifically. We’ll give you both the ups and downs, and as always our recommendations. Lastly, our attempt is not to compare the Atmos Mission One with other freediving watches, but to review how it stands on its own in the freediving world.

Note that the Atmos Mission One has Scuba and Tech functionality as well but we won’t discuss that here.

Reading Time: 9 minutes

Atmos Mission One
The Atmos Mission One in action during a freediving session. Picture by Thibault Guignès.

Atmos & Company

Atmos is a small and innovative company based out of Taiwan that manufactures diving watches. We were very intrigued by their latest model: the Mission One diving watch. Aside from having Air, Nitrox and Gauge modes for scuba and technical diving, the Mission One offers a sweet freediving mode.

In fact, we feel like this is only watches for witch the freediving mode is exceptional. Not many diving watches can stand out in every category, and offer high quality design and functionality.

In this article, we put our Freedive Wire methodology to action. We tried, tested and reviewed in as much details as possible the Atmos Mission One.

We don’t hold anything back: we mentioned the good, the bad and our recommendations.

Mission One Freediving Watch

Design and Use

The design is very intuitive. Even without reading the user manual you will be able to understand the basics of most functions. Of course, we recommend you read the manual to take advantage of all the features. You can easily navigate from menu to menu, customizing any features. The four buttons are easy to use, even with thick gloves.

The battery life is also very good and the battery lasts for about 5 dive sessions. This is using the freediving mode, the stopwatch time, alarms and other settings throughout those days. Recharging is easy and intuitive with a USB cable plugged into your computer or outlet.

Comfort and Fit

We love the small details in things. The double watch strap keepers add extra security if you decide the tie off the watch to your neck-weight during descent. In addition, one of the keepers has a little notch, to “lock” into place in the adjustment holes. It is an almost unnoticeable feature, and this is the kind of thoughtfulness we love to see in product design.

The silicone watch strap sticks very well to freediving wetsuits. Whether you wear Smooth Skin Composite (SCS) or lycra/nylon lining exterior. The silicone strap make a good grip on your wrist and doesn’t move around.

Depth and Time Alarms

This is where the Atmos Mission One is golden in our opinion.

With 10 sets of time alarms and 10 sets of depth alarms, you can fully customize these options for training and competitions. For deep hangs we enjoy having several time alarms to remind us to relax during the dive and for safety reasons. For deep dives, having several depth alarms is necessary for negative buoyancy depth, mouthfill, reminder to relax, depth left to go, etc.

Two recent dives where these alarms where handy, for example:

  1. Deep hang at 50 meters (164 ft): A depth time alarm at 1:00 min to signal arriving to depth on time. A second alarm at 1:45 min after a 45 second hang (to remind you it’s time to go up).
  2. Bi-fins dive to 65 meters (213 ft): One depth alarm at 10 meters (33 ft), one at 20 meters (65 ft), one at 55 meters (180 ft) and a final one at 60 meters (197 ft).

Finally, the combination of both noise and vibration alarms is excellent. There’s the option for only one, or both simultaneously. In particular, the vibration is such that you can feel it very well even with a wetsuit on. This avoids having to place the watch “under the hood” or tied to your neck weight.

The Atmos Mission One freediving watch.

Deep Safety Features

For deep freediving mode, there is a feature that recommends “no fly” just as in scuba. This is an excellent reminder that in deep freediving you can also build up nitrogen in the body, and should not fly or scuba afterwards. This level of safety and conservatism is very much appreciated in afreediving watch.

However, we also like that you can “reset nitrogen” after deep freediving so it doesn’t display on the home display. It’s a reminder, but it doesn’t fully constrict or “lock you out” from diving.

Surface Interval Alarm

The surface interval alarm is quite nicely integrated. A simple alarm reminds you when it’s safe or not to continue on your next dive. This is especially important for deep freedivers that intend to do several deep dives per session.

We strongly suggest to never solely rely on any dive computer to tell you when it’s safe to do your next dive. However, having this alarm is a great reminder to follow the safety protocol and take a good rest in between dives.

As far as we can tell, this alarm follows the standard AIDA International guidelines taught in AIDA courses:

  • 0 to 29 meters (95 feet): surface interval alarm is double your last dive time
  • Beyond 30 meters (98 feet): surface interval is your dive’s depth divided by five (i.e. 30 meters / 5 = 6 minutes)
  • Beyond 50 meters (164 feet): no warning to stop diving for the rest of the day, (please use your own judgement and experience here)
Atmos Mission One
A very comfortable Atmos Mission One sticks well on your SCS neoprene wetsuit.

The Atmos App

The Logbook

The logbook on this freediving watch is easy to access through the settings. You can review each dive individually, or look at the deepest and longest dive of the session. Clicking on the individual dive shows the time, the dive time, the maximum depth and the dive profile.

We like that each diving profile can be individually reviewed on the watch. This includes important information such as depth, time and dive speed at each point of the dive.

This intuitive feature is very useful for instructors or deep spearfishers that need immediate feedback for safety or dive adjustments. It might show you that you can slow down your descent, or should spend less much time on the bottom. It can also indicate (and confirm) a down and upwellings.

Application (App) Interface

The options of uploading the divelog on your smartphone and seeing each detail is excellent. Being able to analyze the dive profile is very important, for education and safety reasons. The app is easy to download (Apple Store or Google Play) and allows for syncing via bluetooth.

On the smartphone app you can see all the diving info in greater detail. You can easily analyze the details of each dive charted on the profile. Air and water temperature, maximum and average depth and dive duration are all included. Furthermore, you can customize each dive by adding data such as weather conditions, geo-location and pictures.

Our Recommendations

We’re very happy with the Atmos Mission One as a freediving watch, however we can definitely suggest a few recommendations.

  1. Have interval depth alarms
  2. Alarms active during ascent
  3. Improve the usability of the mobile app

In more detail:

  1. An interval alarm system can be a valuable option. In addition to having the regular depth alarms, the user can simply set interval alarms. For example, a simple command dictating you want at every 10 meters on the descent and ascent. Many deep freedivers, including my training buddy Thibault Guignés enjoy this style of alarm system.
  2. Setup the regular depth alarms so they signal during the ascent as well. Many deep and competitive freedivers enjoy this style of alarm system. It’s an additional and simple feature to offer for the freedivers.
  3. Downloading the mobile app and creating a profile was a little tricky. The interface can be confusing initially. There’s also a few simple glitches on the app, for example when the app is “scanning” for devices and updating a form entry. Linking and pairing the device with the app is very straightforward, however and the syncing of data is very well done. Overall, our recommendation is to focus on streamlining the interface so it’s easy to use by any user.

During the writing of this article Atmos released a new version of their firmware (v. 1.017). The Atmos Mission One Tool is a desktop app that updates your watch anytime new features or versions are released.


The specs provided here by the manufacturer. For more info check out Atmos’ website.

  • 5 modes available: Air|Nitrox|Freedive|Gauge|Off
  • Water resistance: 100m (10ATM)
  • High-resolution 1.2” (30.5mm) color display (Sunlight-visible)
  • Easy to read screen and big layout display
  • Highly intuitive user interface
  • Multiple languages offered
  • Vibration alarm along with sound alarm
  • Digital compass
  • Mark entry/exit GPS for site location recordings
  • Dive spot guide (surface use only) perfect for freediving
  • Dive log memory: 100 dives logged
  • Smart notification (iOS & Android)
  • Digital divelog with diving profile and playback
  • Firmware update via USB cable to computer
  • Rechargeable with USB cable
  • Silicone strap (24mm width compatible)

Luca Malaguti

Luca Malaguti is a former engineer turned freediving professional athlete and founded Sea to Sky Freediving. He lives in Vancouver, Canada among other places including Dahab, Dominica and Philippines.

This Post Has 7 Comments

  1. Ralph Maurin

    Could you tell us if we can chose at what depth the watch start?
    and could we choose a specific depth (exemple 1 meter or 0.5 meter)
    I am just wandering if we could use it on pool also,,,
    Thanks for your answer

    1. Luca Malaguti

      Hello Ralph,

      You can actually adjust that depth in the system settings. You can set at which depth the depth gauge is “triggered”.


  2. Alexandre Witschi

    Hello, I need to use this watch as a “chronometer” to time students in the pool, so far I did not find any info about that feature, can you tell me what’s possible to do? If I have 2-3 student simultaneously can I record individual times as well?

    1. Luca Malaguti

      Yes you can!

      Please read manual. There’s a chrono with lapse.


  3. Dan Pelchat

    Hi Luca, I just purchased the Atmos Mission One for freedive safety at Howe Deep contest in Vancouver BC. I cannot get my GPS to connect. I tried the obvious open sky and phone sink. Any advice to help the watch find a link so I can log the location?

    1. Luca Malaguti

      Hey Dan,

      Happy to hear you figured it out! There’s been improvements and the Atmos Mission 2 works even better!



  4. Dan Pelchat

    Update on my last post about the GPS. It is now working fine. I am very happy. All the best

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