Matrix Powerwatch review

A smartwatch that’s charged entirely by your body heat

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Specs, performance and fitness

  • Can track your step count, sleep duration and distance
  • Won't track cycling, swimming or other activities
  • Very limited smartwatch capabilities

We don’t know much about the internal technology powering the Powerwatch, but it’s not going to be able to do everything a top-end smartwatch like the Apple Watch 3 can.

Obviously it can tell the time - as any watch should - but the smart features here are limited.

Heading through the menus, you'll have the option to see your Daily Activity, allowing you to track your step count throughout the day, Running Mode meanwhile will monitor your jogs, and Stop Watch will time your workouts.

There's no heart rate monitor on this watch, which is a little strange considering there's seemingly plenty of room for one, though perhaps the charging tech (detailed below) prevented one.

It’s not a watch built for running in particular either as the strap is uncomfortable when you’re sweating and it doesn’t record many details.

The watch will record the distance you've run, but it doesn't use GPS so you may be a touch skeptical about its accuracy. We ran with both a GPS watch and the Matrix Powerwatch on and found a similar distance, but we wouldn't recommend this if you need your distance recorded on every run.

One of the reasons for that is the app doesn't provide any in-depth details. Lots of GPS running watches can show where you've been on a map, but here all you'll get is the distance as a number.

The watch will also show you the estimation of calories you've burnt, your step count, the distance you've traveled and how long you've slept. 

There's no further breakdown of the information though, so unlike on most other fitness tracking apps you won't get information on your sleep quality or when you made the most progress on your step count.

We found the Powerwatch's app particularly frustrating, partly because it's difficult to navigate, but there's also just a lack of depth in the app, and that's something we'd love to see Matrix improve for any of its upcoming watches.

Another interesting feature is that the Powerwatch can tell you your temperature, which will obviously fluctuate depending on how much you’re exercising. But there’s no way of using that number for anything specific.

Instead you’re greeted by the temperature of your skin and we’ve yet to find any real use for that number apart from knowing how warm we are when working out.

It’s also running or nothing here. There’s no tracking for swimming or cycling despite it being an interesting device for both of those sports and being waterproof.

For the amount of money you’re spending here, you can get a suitably good Garmin watch, Fitbit Versa or a specialized running device that will be able to track you a lot better with far more stats.

Unlike the Fitbit Versa, you won't be able to get notifications through to your wrist and there's no onboard storage or Bluetooth connectivity, so you can't listen to music when running unless you bring your phone with you.

Matrix has said you'll be able to change the watch face soon to personalize it to your look, but that's not something we've been able to test yet as it has yet to be made available.

Battery life

  • Incredible new technology that charges using your body heat
  • Means you'll never have to put the Matrix Powerwatch on charge

The headline feature here is how you can charge the Powerwatch. Simply wear it and the heat from your arm will then charge up the watch as you use it. 

It uses a proprietary thermoelectric energy converter on the back of the watch which is smart enough to use your body heat to power it, but you wouldn’t know it by looking at the rear of the watch.

It’s flatter than if there was a heart rate tracker there. The watch is meant to last several months without you wearing it too. If you’re not wearing the watch for a certain length of time, it will go into a sleep mode to help preserve the battery.

We left the watch for a month or so, and when we returned it still had enough charge to get us started, so you shouldn’t have to worry about whether it will be able to work right away if you haven't worn it for a while.

As much as we’ve struggled to love the Matrix Powerwatch’s smartwatch features, it’s really commendable that the company has managed to package this new technology into a watch.

Imagining this kind of tech inside a fully fledged smartwatch would be a game-changer up against the likes of the Wear OS market and Apple Watch brigade.


There’s no denying the technology behind the Matrix Powerwatch is a great step forward for providing battery to your wristwear.

Not having to pack a charger in your bag when you go away on holiday or remember to place it on your bedside at night is a big benefit, and we can see this technology going far.

As a proof of concept, the Matrix Powerwatch is a very interesting device, but it’s not a fully fledged smartwatch and we wouldn’t recommend this to anyone unless you really want to try out that new battery technology.

Who’s this for?

This is for those who want to get an early taste of a new battery tech that can charge just by using the heat of your skin. There’s very little else the watch can offer though.

If you’re looking for a step counter that doesn’t need recharging, this may be up your street. But that said, you can buy a variety of hybrid watches that last for six months or more from a single watch battery that would be able to offer you more stats.

The fact this watch is run on your heat but can’t monitor your heart rate is ludicrous to us, and considering devices half the price are capable of monitoring your heart rate accurately we can’t recommend this as a fitness device.

Should you buy it?

Only if you think this groundbreaking new technology is something you need on your wrist today.

We don’t love the design of the Powerwatch and its fitness features are very limited. The battery tech is mind-boggling when you consider we sometimes use smartwatches that can only last a single day, but right now this is just a proof of concept device.

Instead of going for this, you should probably opt for a running watch to monitor your fitness or a hybrid to keep track of your step count in style while offering battery life that's almost as great.

If this battery tech is exciting to you, you’ll want to watch whatever this company does next and hopefully we’ll see the tech debut on a fully fledged smartwatch that’s worth buying at some point in the future. If we do, it may just change the wearables space for good.

First reviewed: July 2018

James Peckham

James is Managing Editor for Android Police. Previously, he was Senior Phones Editor for TechRadar, and he has covered smartphones and the mobile space for the best part of a decade bringing you news on all the big announcements from top manufacturers making mobile phones and other portable gadgets. James is often testing out and reviewing the latest and greatest mobile phones, smartwatches, tablets, virtual reality headsets, fitness trackers and more. He once fell over.