Withings' new watch looks so nice you'll miss its best feature

The company's sleek timepieces often belie how much they can actually do.

You may know Withings as the company that pioneered WiFi scales. I know them as the people who make beautiful fitness trackers. At a glance, their watches all look like classic analog timepieces, with leather bands and round screens that never feel too large. The new ScanWatch, which made its debut this week at CES, is more of the same. Which is to say it's pretty, and also can do a lot more than than its timeless design would have you believe.

On the back side of the watch is a pair of optical sensors: one to detect arrhythmias, or irregular heartbeats, and another for detecting sleep apnea. That latter feature is particularly interesting. Whereas ECG tests have become standard on smartwatches and some fitness trackers, few today can detect sleep apnea, a sleep disorder that can increase one's risk of various fatal outcomes, including strokes and heart attacks.

To pull off this apnea test, Withings used an optical sensor that measures oxygen saturation in the blood. As you can imagine, I was not able to test this feature when I got hands-on with the device here in Vegas (for one, I do not have sleep apnea, and also, I was awake). Better to let regulators be the judge of that. The ScanWatch is awaiting certification from the FDA in the United States and the EMA in Europe. Withings hopes the device will be ready to ship sometime in Q2 of this year.

If you've seen an Apple Watch Series 4 or Series 5 in action, the ECG test here should feel familiar, if not in the graphical user interface, then in the basic simplicity of it. In a demo, a company rep held down the button on the watch's upper-left edge and then held her fingers around the "eight" and "one," in analog clock terms. The wearer's heart rhythm scrolls across the screen. Hopefully, for your sake, it's regular.

Like other Withings watches, the ScanWatch is a basic step tracker, with built-in GPS, tracking support for over 30 sports, and a waterproof design making it safe to use in up to 50 meters of water for up to 10 minutes. In other words, if you want a watch for lap swimming, this might not be the one for you.

The watch is available in two sizes: 38mm and 42mm. Each comes in white or black. The 38mm model costs $250 (€250 in Europe) while the 42mm is a bit more expensive, at $299.