- Speedy, slick software
- Improving companion app
- Solid week of battery life
- NFC payments setup didn't work
- Continuous heart rate tracking accuracy
- Dual-band GPS wasn't super accurate
The Xiaomi Watch S1 is the company's latest flagship smartwatch, which comes with stainless steel case with sapphire glass, but still comes in under £200/€200.
Joining the sporty-looking Watch S1 Active, the Watch S1 offers pretty much all of the same features albeit wrapped up in more high grade materials.
Those features include an AMOLED touchscreen display, blood oxygen monitoring, over 100 fitness modes and dual-band GPS mode to improve outdoor tracking. There's also built-in Amazon Alexa and NFC contactless payments via Mastercard.
That means that Watch S1 is up against some big names. So, does it offer a better smartwatch experience than Apple, Fitbit and Amazfit? We've been putting it to the test to find out. Here's our comprehensive verdict.
Xiaomi Watch S1: Design and screen
With the Watch S1, you're getting a 46.5mm case that measures in at 11mm thick and weighs in at 52g. That case is made from stainless steel and there's sapphire glass dropped on top of a 1.43-inch AMOLED touchscreen display to offer some extra screen protection, which you don't get on the Watch S1 Active.
It's not the most exciting smartwatch to look at, but the materials, screen and the strap offer a smart look that felt nice to wear day and night and during exercise.
Unlike the Watch S1 Active, Xiaomi throws in both a leather and flurorubber strap, which is offered up in a few of different colors. We quickly switched in the flurorubber one as the leather strap didn't quite offer a snug enough fit for the sensors. The pin mechanism at the back does mean it's nice and easy to swap straps in and out.
Xiaomi has stuck to the same screen size and quality for both its Watch S1 and S1 Active watches, giving you an AMOLED that's sharp, offers accurate colors and good visibility indoors and outdoors. You can set the screen to be always-on too, though it will noticeably eat into battery performance. There is a black bezel surrounding that display though Xiaomi disguises it well to make it feel like it's part of the overall look.
It's a responsive screen as well with no worrying signs of lag thankfully. When you're not tapping and swiping, there's two physical buttons to wake up the screen and access the workout screen out of the box. The top button looks like a watch crown and while you can twist it, that doesn't let you scroll through screens.
The 5ATM waterproof rating means you can shower and swim with it up to 50 metres depth. We've showered and taken it into the pool and had no issues using the watch after that time.
What you're getting with the Watch S1 is a nice-looking smartwatch that isn't hugely memorable among other smartwatches around this price. You are getting a good quality screen and the option of two straps is a nice bonus too.
Xiaomi Watch S1: Sports tracking
The Xiaomi Watch S1 has everything to make it a pretty comprehensive sports watch. Once you've swapped in the sporty strap, you're good to run, swim and do some HIIT and this watch will do an okay job of tracking your progress.
In terms of what Xiaomi offers, there's 117 fitness modes and 19 of those modes offers real-time metrics that are specific to that activity. So, it goes beyond tracking heart rate and workout duration.
Xiaomi also includes an automatic exercise tracking mode and it did a reliable job of capturing when we'd broken into a walk, in the same way that Samsung's Galaxy Watches quickly lock on to detecting walks.
For indoor workouts, there's accelerometer and gyroscope sensors to track movement and you have an optical heart rate sensor to track effort levels during workouts too.
When you head outside, Xiaomi has included dual-band, multi-system GPS support. That's a feature we've started to see crop up on more smartwatches and sports watches and is designed to let your watch use extra signals from supported satellite systems to improve location tracking accuracy. Xiaomi can communicate with GPS, Glonass, Galileo, BDS, QZSS satellite systems.
GPS tracking compared: Xiaomi Watch S1 (left) and Garmin Epix Gen 2 (right)
In practice, we didn't quite see that exceptional accuracy. We put it up against the very accurate Garmin Epix (Gen 2), which includes superior multi-band GPS support. In a woody, trail run, tracked routes generally seemed to match up, overall distance tracking came up short and some of the core running metrics attached to it weren't the most reliable.
If you care about heart rate accuracy during exercise, we found that it was hit and miss in places. Below is sample data from an interval track running session against a MyZone MZ-3 heart rate monitor chest strap. It actually didn't perform too badly when pushed at intensity, so that's definitely a plus here on the tracking front.
Exercise HR tracking compared: Xiaomi Watch S1 (left) and MyZone MZ3 (right)
Like the S1 Active, some steadier paced runs and general workouts did see maximum readings and average readings coming in with lower readings, though the strap fit was good for us and clearly that helped with the heart rate tracking performance.
Away from running, we also spent some time indoor rowing, getting sweaty with some HIIT and we jumped into the pool with it as well. It performed well for swims too, offering similar data to Garmin's Epix (Gen 2). Garmin's swim tracking is generally some of the best you can find, so it's nice to see Xiaomi managed to match up. You can also get more metrics from your swim in the companion Mi Fitness app if you want to delve deeper into your swimming session.
Pool swimming compared: Xiaomi Watch S1 (left and centre) and Garmin Epix (right)Xiaomi has dropped the Firstbeat training insights it included on the Xiaomi Mi Watch, but does still include support for Strava, which means you can fire your data over to the platform and it does that in a speedy fashion once you've completed a workout.There's some definitely some good and not so good parts of Xiaomi's sports tracking. The dual-band GPS didn't quite live up to its accurate billing, though it did perform well for pool swims and for tracking heart rate as well. Ultimately though, it doesn't rival the performance of a similarly priced Garmin, Polar or Coros sports watch.
Xiaomi Watch S1: Fitness and wellness tracking
The Watch S1 can act as a fitness tracker and there's some wellness features thrown in for good measure too. If you want to track steps, sleep, stress, heart rate and blood oxygen levels, this watch can do it.
If you care about counting steps, there's a nice dedicated widget to show off your progress, which also displays standing time and calories burned during the day. The watch will throw up an animation when you've been inactive for too long as reminders to keep moving.
Step tracking compared: Xiaomi Watch S1 (left and centre) and Oura Ring 3 (right)
We wore the Watch S1 alongside the Oura Ring 3 and found step counts in general were pretty similar. It was a similar story on days where we threw on the Garmin Epix to compare step stats too.
When it's time for sleep, there's a dedicated widget to see the previous night's sleep, breaking down sleep duration along with heart rate and blood oxygen data if you've enabled the monitoring in the companion app. Turning on the heart rate and blood oxygen monitoring does eat into the battery and you'll be told that before you turn them on.
Sleep tracking compared: Xiaomi Watch S1 (left) and Oura Ring 3 (centre and right)
We wore the Watch S1 with the Oura Ring 3, which we've found to offer sleep tracking accuracy on par with Fitbit and Polar in our testing. What we found in general is that sleep duration numbers and sleep stage breakdowns were pretty similar on most nights.
Like the Xiaomi Watch S1 Active, we found sleep heart rate a little higher, but on the whole the sleep tracking accuracy seemed pretty good to us. The presentation of the data is pretty much in line with most trackers. Xiaomi doesn't go big on insights and recommendations, but we imagine that'll come in time.
If you care about continuously monitoring heart rate, we'd say this isn't a strength of Xiaomi's on the Watch S1. You can view real-time readings, heart rate highs and lows and time spent in heart rate zones from a nicely-designed watch widget.
Heart rate tracking compared: Xiaomi Watch S1 Active (left) and Oura Ring 3 (centre and right)
When we dug into the data in the companion app and compared to the heart rate monitoring on the Oura Ring 3, we found that in general heart rate readings were 10bpm higher. It was a similar story comparing it to a chest strap monitor and with the continuous monitoring on a Garmin watch.
On the health and wellness tracking front, Xiaomi does also include women's health tracking features to track menstrual cycle and ovulation phases.
Xiaomi can also monitor blood oxygen levels both the on the spot kind and continuously. While data seemed generally reliable compared to a pulse oximeter there isn't any sort of actionable insights attached to that monitoring.
There's stress tracking here too, which is driven by heart rate variability measurements and scoring your stress on a numbered scale. The lower the better is the key and you'll get a breakdown of daily stress and time spent in stressful periods. You can pinpoint stressful periods in the day, and take advantage of the guided breathing exercises, which are available on the watch.
The Watch S1 performed well as a fitness tracker. For steps and sleep it offered reliable data, though it struggled for us with continuous heart rate monitoring and in general lacks some actionable insights that would be helpful for newcomers to fitness tracking.
Xiaomi Watch S1: Smartwatch features
The Watch S1 we'd say does a good enough job as a smartwatch. It gives you what you need and there's some desirable extras here like Amazon Alexa integration and Xiaomi Pay for contactless payments.
It does work with Android phones and iPhones and our time was spent using it with a Samsung Android phone. It was nice a straightforward pairing it up to the now rebranded Mi Fitness app and we didn't have to wait on achingly long software updates to install before being able to use it.
Before putting its smartwatch features to use, it's worth spending some time in the companion app, which still has that huge avatar guy (he's bigger this time), on the Health tab, which is followed by the Workout tracking, Device and Profile tabs.
In the device section you can pick from a rich collection of watch faces, with more available online. These include animated watch faces as well, though be mindful that these will suck a bit more battery than the static ones. Unlike some watches, firing over new faces to the watch works really quickly.
This is the same place you can set up Amazon Alexa, decide which notifications you want to receive and turn on/off incoming call alerts. You can also set up weather forecasts, Bluetooth calling and to our surprise, there are some apps here too. They're not the third party kind and there's not many, but we did install a scientific calculator and a number puzzle and again, they installed pretty rapidly onto the watch.
The notification support is perfectly fine too. You can swipe down from the main watch screen to view your feed and you can clearly identify where they've come from and are well optimised for the display. You can't respond to notifications. There's music controls but no built-in music player, and those controls worked without issue when we fired up some music on our phone.
As mentioned, there is support for contactless payments through Xiaomi Pay, which works via Mastercard and requires setting up a 6-digit pin on your watch to make sure someone can't pick it up go. After several attempts to add a card and set it up, we repeatedly received an error message so there's clearly some bugs to iron out here.
The on-watch experience on the whole is straightforward and it has a distinct feel to it. There's an app grid and swipes from the main screen get you to features like your notification stream, widget screens and quick settings panel. You can switch that app grid to a list, which does make it easier to identify what features the icons represent.
Xiaomi isn't breaking new ground, but it does offer a solid smartwatch experience for the price. It does clearly need to to take a look at that payment support though.
Xiaomi Watch S1: Battery life
Our battery experiences with the Xiaomi Watch S1 mirror pretty much what we experienced on the Watch S1 Active. This smartwatch can deliver a solid week and can go longer. You'll just need to consider ditching battery-hungry features like advanced sleep monitoring and continuous blood oxygen monitoring to go further.
That's probably because you're getting the same 470mAh capacity battery, which Xiaomi says get you 12 days in standard mode and up to 24 days in standby mode. Unlike the Active though, you do get wireless charging support here to give you more charging options away from the disc-shaped one included in the box.
We experienced around 5% daily drop-off in battery with the screen not set to always-on and without turning on the advanced sleep monitoring, continuous blood oxygen monitoring and chose to sample heart rate data continuously on a more regular basis. That doubled the daily drop-off.
When using the GPS for outdoor tracking, an hour of running saw battery drop by 10%, giving you around 10 hours of GPS battery life based on our testing. For over an hour of treadmill running, the battery drop-off was around 2%, which isn't all that surprising given motion sensors aren't hugging the same level of power.
So the battery performance is solid if you can live with a week without charging. Even when you turn on the features that you'll be prompted will suck more battery, it still doesn't limp from getting from Monday all the way through to Sunday.
How we test