Xiaomi Watch S4

Xiaomi has in almost record time established itself as one of the world's biggest tech companies, so big that in 2014 it managed to become China's largest phone company. This is quite a feat considering they launched their first phone just three years earlier, a year after they were founded. In the European market, their sub-brand Redmi is probably better known. If the free market had been a bodybuilding competition, there would definitely have been a drug test. As a major player in the market, it makes sense to have and offer customers a complete ecosystem, and that includes smartwatches.

Xiaomi has always strived to deliver the best and latest technology at the lowest possible price, and the S4 Watch is no exception. The price here goes down to as low as £130. However, I'm struggling a bit with Xiaomi's naming. Their other watch is called Watch 2, there are GT and Pro versions, and the other variants they have are under the Redmi brand.

For the relatively low price of £130, you get a 466x466, 1.43" AMOLED display, and a surprisingly well-built watch. The design is very classic and although it's very individual, I'm actually glad they tried to use large icons instead of the small ones, which are unreadable on many other watches. The pixel density is relatively high at 326 PPI and the watch has 1,500 nits of brightness with a peak option of 2,200 nits. My only criticism is that the colours, or rather the icon colours, are a bit dull - I wish more bright colours were used. The crown of the watch can rotate, but that in itself isn't revolutionary unless you're writing sales pitches for this particular watch.

One of the watch's distinguishing features is its ability to change appearance. We're not just talking about a new strap, but also the dial itself can be changed, and you can even get complete packages where everything fits and matches. Yes, some items can't be bought separately, but can only be bought as a complete package. It's pretty elegant and I love the concept. By default, it comes in several designs and with a lovely aluminium frame. It's nice, but the build quality and especially the user interface of the watch needs some finishing touches to be on par with the more expensive models. The battery life is impressive and we managed over two weeks with regular use.

The accompanying app is called Mi Fitness and I have to say that the number of permissions needed to get it to work was quite overwhelming. It's functional, but that's about it. It's all a bit too standardised, and I would have liked to see more time spent on developing a more attractive app design, not to mention a few more watch faces, which it lacks. As I said, it's quite functional though. It supports something like 150 sports, dual GPS, and there's even a dedicated ski mode with fall alert and everything.

Unlike others, there is also support for VISA and Mastercard payments through an NFC chip. However, I have to admit that I haven't tried it locally for the simple reason that I don't like paying by watch, it simply makes it too easy to spend money.

There is a better piece of software called Xiaomi Smart Hub, but it's only available with a newer smartphone of the same make that supports HyperOS 2. I don't know what's missing in terms of functionality that way, but to omit an entire app and tie it to the use of the same brand of mobile phone seems a bit odd.

Where the watch is lacking - and it could well be me who got a faulty copy or forgot an important update - is the heart rate measurement... It's not good. In fact, it doesn't work at all, unless I've magically got into amazing shape and actually weigh 20kg less than I thought I should. It's a similar story with Bluetooth playback from the watch's internal memory: it coughs and stutters like an old tug boat and is filled with digital noise like an old dial-up internet connection over telephone cables. It simply can't be right, it must be a bug. Especially because it renders the watch completely useless for exercise, which doesn't make much sense as it counts calories and steps as it should. And in my world, exercise and activity logging is probably one of the most essential things a smartwatch should do.

So, we'll land on a score now, and if there's an update that fixes these very basic bugs before the test sample is sent back, the review and score will be changed to reflect that. We have tested Xiaomi products before, including recently, and they tend not to have functionality issues.