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Matrix Powerwatch X review: Infinite battery... but what's the cost?

Matrix Powerwatch X runs off body heat. That's the best thing about it.

Scott Stein Editor at Large
I started with CNET reviewing laptops in 2009. Now I explore wearable tech, VR/AR, tablets, gaming and future/emerging trends in our changing world. Other obsessions include magic, immersive theater, puzzles, board games, cooking, improv and the New York Jets. My background includes an MFA in theater which I apply to thinking about immersive experiences of the future.
Expertise VR and AR | Gaming | Metaverse technologies | Wearable tech | Tablets Credentials
  • Nearly 20 years writing about tech, and over a decade reviewing wearable tech, VR, and AR products and apps
Scott Stein
4 min read

It's handy to never need a watch charger.


Matrix Powerwatch X

The Good

The Matrix Powerwatch X has an effectively infinite battery life, powered by your body heat. An always-on screen shows time, steps and basic notifications. It's also water resistant to 200 meters.

The Bad

Its bulky design won't appeal to all wrists. Notifications don't show the content of messages. Bluetooth syncing and pairing doesn't always work. Its fitness features are extremely basic, making this more of a step and calorie counter. It only has one watch face.

The Bottom Line

The no-charging-needed Matrix Powerwatch X shows a future of infinite-battery wearables, but this isn't the watch to buy.

Smartwatches are frustrating for many reasons, but the need to constantly recharge them is the worst. Some watches are finding ways to last more than a week, such as the Amazfit Bip. But what about lasting forever?

The Matrix Powerwatch X is a watch that's powered entirely by body heat. Thermal gradients, to be precise. The watch uses the difference between skin temperature and the outside air to generate a current that activates and charges everything. Sound weird? It is. Maybe it's the future of a world of wearables where everything is body-powered. Like... oh, yeah, that's why the company is called Matrix Industries.

I first met with Matrix Industries a couple of years ago. Its first product, the Matrix Powerwatch, debuted in 2017. The Matrix Powerwatch X is a more advanced watch, with step counting, sleep tracking and buzzing notifications.

I'd love a watch to last forever and be great. The $280 Powerwatch X does one of these things. 

The big, bulky look of the Powerwatch X is eye-catching. It's like a supercharged metal version of a G-Shock. But it won't appeal to everyone, that's for sure.


That's a big watch.

Sarah Tew/CNET

Sturdy design, crazy thick

If you're not into super-sized watches, read no further. Wearing it made me feel like a bit like a dad commando.

The ridged outer casing has a purpose, though. The ridges act like a heat vent. The watch doesn't get hot, or even warm, but the case has a subtle two-part design between the inner and outer layers. A temperature differential is helped by the heat vents, which are silent, with no fans. These are like heat sinks on computers.

A rubber watchband felt surprisingly comfy on my wrist. Despite the watch's thickness -- and tendency to cause my wrist to sweat in humid July New York weather -- it was easy to wear.

The watch is also water-resistant up to 200 meters, which at least means it's pool-friendly. But it won't track swimming.

Sarah Tew/CNET

Always-on display

Think this looks like a Casio G-Shock? Well, the screen looks like one, too.

The Powerwatch X has a standard reflective black and gray LCD, like your '80s digital watch. The recessed display looks crisp, but in dim light can get hard to read. Most watch readouts are gray-on-black, and consist of a single big time readout, or step count, or stopwatch countdown (depending on the mode). There are no extra watch faces on the Powerwatch X, and no way to show multiple bits of information at once, which means frequent watch-fiddling.

There's no touchscreen, either. Two side buttons on the right cycle through watch modes and trigger stopwatch or exercise start/stop controls.

There's a backlight, too, if a side button is pressed. It's dim and only helpful in total darkness.

Sarah Tew/CNET

Super-basic fitness

Steps are counted, and sleep is tracked automatically, too, but only in terms of total hours and minutes slept. Matrix's phone app for iOS and Android is extremely basic and lacks helpful charts and detailed breakdowns that show up with most fitness trackers. I also found the watch's step-counting to be too forgiving and easily triggered when I was moving or showering but not walking, compared to Fitbit and Apple Watch.

Step count can't even be casually glanced at: You'll have to press a side button to switch modes.

Sure, the watch has a stopwatch, and an "exercise mode" that's basically the stopwatch plus a simple activity-tracking timer for steps and distance. The stopwatch and exercise modes can't run in the background, though.


Yes, it knows your skin temperature (or, an approximation)

Sarah Tew/CNET

Notifications... or notifications that you have notifications

The Powerwatch X will buzz to indicate incoming calls, text messages and email. But, the large display doesn't show actual messages, just an icon that a message came in. This renders the idea of watch notifications useless.

I also found the watch's Bluetooth connection to be buggy, wavering in and out. On an iPhone X, the watch seemed to drop off and be offline several times even when I had both devices nearby.

I want forever charging on all my smartwatches

What Matrix is doing is fascinating, and I can't wait to see what's next. I'd love an Amazfit Bip or Pebble-type watch with infinite battery life. Who wouldn't?

I wouldn't get a Powerwatch X right now, because its price and limited features still don't feel worth it. I'd get an Amazfit Bip, which costs far less and still has really good battery life.

But I really do love the idea of a smartwatch that never needs charging. Matrix seems like it's on to something big, if the idea can expand into other trackers and gadgets.


Matrix Powerwatch X

Score Breakdown

Design 6Battery 10Performance 5Software 3Features 4