The Una Watch is an easily repairable smartwatch that’s held back by a dated design and not-so-smooth software performance.

• Capable of good general sports tracking
• App store can help bring new features
• Una makes it easy to replace components
• Charges via USB-C

• The watch software is laggy
• The design isn’t particularly sleek
• You can’t use it for swimming

• 

• Easily repairable The Una Watch makes replacing elements like the screen and battery a doddle.

• Solid battery life The Una Watch promises between 7 and 10 days of use on a charge.

• Open-source software The open-source software means apps can add entirely new features.

The Una Watch wants to be the answer to wasteful smartwatches.

Instead of trying to convince you every year to buy a new watch, this smartwatch comes with the tool you need to upgrade the watch yourself. You can replace the battery, display and even individual sensors.

The startup behind it has opted to take an open-source approach to the watch software, which means developers can build apps to enhance what the Una Watch is capable of.

This isn’t the first modular smartwatch that tried to change the way we think about how long a smartwatch should last. Previous efforts have failed, so can the Una Watch change that? I’ve had it on my wrist to find out.

Design and comfort

• Available in one case size 
• Not suitable for swimming 

The first thing I’ll say about the Una Watch is that it feels a little bit like stepping back in time and picking up an old Garmin watch. From the predominantly black look to the presence of a transflective, memory-in-pixel display, it all feels a bit old school. 

If you’re hoping you’ll be able to swim with this watch, it doesn’t carry the necessary waterproof rating to allow that. It’s an IPX5-rated watch, which means it can handle some splashes and join you in the shower, but not much else.

What it does have is four physical buttons well spaced out around its not too hulking 40mm-sized watch case. You’ll also find a side-mounted USB-C port as your means of charging, and is likely one of the reasons this isn’t a swim-proof watch. The 20mm removable strap has a nice stretch to it and uses a traditional watch buckle to keep it securely in place.

The memory-in-pixel display measures in at 1.2 inches with a 240 x 240 pixel resolution. That’s similar screen technology you’ll find on watches like the Garmin Forerunner 245, which launched over 5 years ago. There’s mineral glass to provide some protection against scratches and an LED backlight to illuminate it when you’re in more challenging, low-light conditions.

It’s not the brightest or crispest memory-in-pixel display, but it’s been fine to use at night and on early morning outings. I’d definitely take a bit less bezel though, which does eat into the available screen estate.

On the back you’ll find the optical sensor array to handle tracking your heart rate and a series of small black screws. This is your means to gain access to the watch internals, which Una says you can replace yourself. 

Getting the case back off doesn’t take long with the Torx tool that is provided. I was able to lift out the battery without issue, with minimal fuss. When I placed the battery back and screwed everything back in, it managed to reset the watch date and time. Once I synced it back to the app, it corrected things.

The big question here is, where do you get the replacement parts? Currently, Una provides some of them. A replacement display costs £30 while a new battery is priced at £20. That’s certainly going to end up being cheaper to do than buying a new watch. Una as yet doesn’t offer other components beyond the display and battery, so you may have to do some research to work out how to replace other parts until it does.

Software and features

• Uses open-source software platform 
• Works with Android and iOS

The Una Watch runs on an open-source platform and uses a FreeRTOS-based operating system. This is the kind of very power-efficient operating system you’d associate with low-cost smartwatches.

Powering that software is an ultra-low-power Cortex-M33 Microcontroller processor alongside 4GB of storage and 2.5MB of RAM. A lot of smartwatches feature gigabytes worth of RAM as opposed to megabytes, and may play a part in why there’s some noticeable lag when moving between screens on the watch.

In terms of the user interface, I’d say Una does a reasonable job on that front. Do I think it’s the slickest, cleanest interface? No. Was it good enough to get to the things that matter? Yes. 

From the main watch face, you can scroll down to get to your widget glances, which is a very Garmin-like approach to displaying widgets for features like notifications or metrics like real-time heart rate and daily step totals.

Holding down the bottom button gets you to the media controls, while the button in the top right gets you into the workout tracking screen. Again, there’s definitely a Garmin watch feel about the approach.

Within Una’s pretty well-designed companion smartphone app lies its own app store, which is only accessible from the companion app. It’s a store that’s open to developers to create apps, watch faces and add-ons that make it feel closest again to Garmin’s Connect IQ Store.

At the time of testing, I counted just under 40 items available to download, all free of charge. You can whack on a Parkrun barcode or play a game on your watch, but it’s definitely early days on the storefront.

Away from tracking, it’s a watch that can display your phone notifications and control music playback. It’s a more no-frills approach that I think a lot of people will be content with. Just don’t expect it to match smartwatches of a similar price.

Health and fitness tracking

• Includes dual-band GPS
• Can pair external heart rate monitors 
• Can share data to Strava

The Una Watch keeps things limited as far as the activities it can track. There are profiles for indoor and outdoor runs, walks, hikes, cycling and a general workout mode to cover everything else. As a reminder, the level of waterproofing means it’s not suitable for swimming.

There are some pretty standard sensors that take care of tracking your movements. That includes a 6-axis accelerometer and gyroscope motion sensors, a barometric altimeter to measure elevation and an optical sensor on the case back to take care of continuously tracking heart rate, including during workouts. You do have the ability to pair external heart rate monitors here, and I was able to pair sensors from Garmin and Polar without issue.

It’s good to see that dual-frequency GPS makes the cut here. That gives it a GPS setup that the likes of Apple, Garmin, Samsung and a host of other smartwatch brands also include. It’s there mainly to improve tracking accuracy in environments that can cause issues with a GPS signal, like being blocked by tall buildings, adverse weather or big trees on an off-road adventure.

I’ve been mainly using the Una Watch for runs, wearing it alongside watches with similar sensors like the Apple Watch and a range of Garmin watches. I’ll start by saying that the GPS tracks post-run have looked pretty solid overall; GPS tracks hugged closely to tracks from Garmin and Apple.

There was a bit more disparity in the numbers when looking at real-time data like pace, with heart rate monitoring managing to match average and maximum readings on a chest strap on some runs. It also posted notably higher maximum readings on some pretty easy-going runs.

Beyond workout tracking, this is a watch that will track your daily steps, floors climbed, and that’s really about it. You don’t get access to any training plans, while the interval training mode is a bit simpler than similar support on other smartwatches. There seems to be route guidance on the way to give it added navigation appeal, so new features are being worked on and getting added.

Battery life

• Up to 10 days of battery life
• Charges via USB-C

In terms of battery life, Una’s watch hosts a 280mAh capacity battery, which can last anywhere from 7-10 days on a single charge. To put that into perspective, similar sub-£200 watches like the Amazfit Active 3 Premium can last up to 12 days, while the Garmin Forerunner 70 can last up to 13 days. So that number is in keeping with the competition.

With the lack of an AMOLED display or much richer features in daily use, there’s less power drain on a daily basis than your typical sports watch. It can last a week and will go longer if you’re only using the GPS tracking a few times a week.

When you’re tracking outdoor activities and putting the GPS to use, tracking battery life maxes out at up to 20 hours – a few hours short of rival watches in this price range. Again though, it’s more than acceptable on paper. That said, an hour of GPS-tracked outdoor running saw 20% drain, working out to a quicker drain than promised.

Charging the Una Watch is more convenient than most smartwatches. It features a USB-C port on the side of the watch case, which means you can use it with a USB-C cable. It’s also a pretty zippy charger as well; I found it took an hour to get from 0% back up to full battery.

Should you buy it?

The Una Watch delivers on its goal to build and launch a smartwatch that I think even those nervous about tinkering with internals will be confident to upgrade this smartwatch once they see how to do it. I also think going open-source and hoping it can build a Pebble-like community to make the Una Watch more useful is a smart move.

The problem is that the watch design doesn’t match up to similarly priced watches, while the performance and software on the watch just doesn’t feel up to scratch in its current state. It’s clearly a smartwatch, though, that is filled with promise.

For other options, take a look at our selection of the best smartwatches.

We thoroughly test every smartwatch we review. We use industry-standard testing to compare features properly, and we use the watch as our main device over the review period. We’ll always tell you what we find and we never, ever, accept money to review a product.

• Worn as our main tracker during the testing period
• Heart rate data compared against dedicated heart rate devices

	Una Watch Review
Manufacturer	–
Screen Size	1.2 inches
IP rating	IPX5
Waterproof	N/A
Battery	280 mAh
Size (Dimensions)	x x INCHES
Operating System	FreeRTOS
Release Date	2026
First Reviewed Date	02/10/2026
Colours	Teal, White, Black
GPS	Yes
UK RRP	£179
USA RRP	$199