Withings’ ScanWatch ($279.99) is a consumer-grade health and fitness device that does far more than just count steps and encourage you to move. The watch, which the FDA recently approved for use in the US, can read electrocardiograms (ECGs) and potentially detect heart problems such as atrial fibrillation (AFib). Its long battery life and analog aesthetics impress, but we found it a bit bulky and it took some time learn how to get usable ECG readings in testing. And unlike the Apple Watch ($399.99), you need a prescription to use the ScanWatch’s ECG features. So while the ScanWatch is among the more attractive fitness wearables we’ve tested, you’ll likely get more use out of the Apple Watch or even Fitbit’s $179.95 Charge 5.
Stylish But Hefty
The ScanWatch differs dramatically from the Apple Watch in style. It is easy to spot the Apple Watch from a distance because it looks like a tech product, but the ScanWatch sports an understated, classy design. The larger variant (42mm in diameter) costs $299.99, while the smaller version (38mm in diameter) is $279.99. Withings sent me the larger model of the watch to test. It looks and feels big, weighing in at 2.9 ounces. My wrists are hardly petite, but I might have been better off with the smaller version that weighs 2 ounces.
The watch’s crystal face is made of durable, virtually scratch-proof sapphire glass. You can choose between a silver case with a white or black face, or a rose gold case with a white or dark blue face. The rose gold color options are only available in the smaller size, however. The outer edge of the watch case functions as a sensor; you press it with your opposite hand to take ECG and SpO2 measurements.
Withings says the ScanWatch should last about a month on battery with normal use. After five days of testing it, the battery was still at 96%, so you shouldn’t need to charge it for several weeks at a time. The long battery life is important because it enables the watch to scan your vital signs periodically and without frequent interruptions. If you significantly pare down the watch functions by putting it into power reserve mode (which supports time and activity tracking only), you can get an extra 20 days of battery life. Recharging the watch from a dead battery only takes about two hours.
The ScanWatch doesn’t include built-in GPS functionality, so you need to use it alongside your phone any time you want to track outdoor activities, such as bike rides and runs, with the most accuracy. Because GPS functionality tends to draw a significant amount of power from other fitness trackers and running watches, the ScanWatch’s battery life may benefit from its absence.
A water resistance rating of up to 5ATM means the watch should survive swimming, snorkeling, and other basic water activities. Just don’t take it on any deep dives. It also won’t fare well in extreme cold or heat; the operating temperature range is 14F to 113F.
The watch comes with a swappable fluoroelastomer wristband; its material feels similar to silicone. You can pay extra for a leather, metal, or woven PET (made from recycled materials) band in various colors. You get a magnetic disc-style USB-A charger, a quick start guide, and a lovely gray felt pouch for storage and travel in the box.
What’s on the Watch Face?
Because the ScanWatch looks like a classic watch, it doesn’t have a bright, digital display. Instead, two circular insets sit behind the two arms that show the time.
The top one looks simply like a black circle until you press the crown; then, the PMOLED display lights up to show your health and fitness data, as well as any notifications from your phone. Turn the crown dial to rotate through the options, such as time and date; current heart rate; step count; distance; and floors climbed. If you continue to scroll through the options, you can take an ECG or SpO2 reading, plus record an activity.
The second inset is a single-arm analog dial that’s useful for quickly glancing at your daily step count without needing to push the crown. The arm slowly circles the dial throughout the day as you move and shows your step count as a percentage. For example, if the arm reaches the three o’clock position, you’ve hit 25% of your daily step goal. The dial marks the 50% and 100% positions for clarity.
Setup Requires a Phone and a Doctor
To get going with the ScanWatch, you first need to download Withings’ Healthmate app (available for Android and iOS). You cannot set up the watch from a computer. The app is free and doesn’t bombard you with any upsells or premium subscriptions offers. When you launch the app and create or log in to your Healthmate account, the first step is to pair your phone with the watch. Then, simply follow the rest of the on-screen setup instructions.
As I mentioned earlier, you need a doctor to read your first ECG and approve you to use that feature. The process is virtual and Withings facilitates it for free. Some states may require you to get on the phone with a doctor before getting approval, but neither the doctor nor Withings will bill you for that call. For more information, check out Withings’ resources on the doctor approval process of your ECG.
The company set me up with a version of the app that didn’t require that step, but for anyone else in the US, the process is fairly straightforward. When the app prompts you to take your first ECG reading, it shows you illustrations on how to hold and position the watch. However, the instructions could better explain that the watch casing doubles as a sensor (when you touch it, you complete a circuit that allows the ECG to proceed).
Once you take an acceptable reading, the Healthmate app sends the data to doctors at Heartbeat Health, who review your results within 48 hours. Heartbeat Health is a separate healthcare technology company that Withings uses to read and validate the results of your first ECG and issue the prescription that lets you use the ECG feature of the watch. Along with the initial reading, you must agree so send some personal information (your name, date of birth, and contact information) to Heartbeat Health, too. Until Heartbeat Health reviews your data and issues the prescription, you can’t see the results of your ECG reading in the app; they remain hidden until you get doctor approval.
If everything goes smoothly and you get approval to use the ECG, you can take as many subsequent readings as your heart desires. ECG results appear in the app and you can export them to share with a doctor. In addition to the ECG, SpO2, and fitness tracking capabilities I explain below, the app can also help you perform a VO2Max assessment and log your weight over time.
Finicky ECG Readings
Although they’re the ScanWatch’s main draw, some still question the usefulness of on-demand ECG readings. One argument is that the type of person most likely to buy a pricey fitness-tracking smartwatch isn’t likely to be someone who would benefit from regular ECG screenings. But if you would benefit due to certain risk factors or age, then this technology can legitimately help you monitor your health. Just know that pacemakers and cardioverter defibrillator implants can cause inconclusive ECG data and that you must be 22 years or older to use this feature. The age restriction is due to the FDA’s policy that teenagers, meaning people 12 to 21 years old, shouldn’t use non-pediatric medical devices because of concerns over safety and effectiveness. Withings says it complies with this policy.
Taking an ECG reading at the right time is far more useful than randomly performing these measurements. The ScanWatch periodically reads your heart rate throughout the day and night. It alerts you if it detects a possible irregular heartbeat, and, in that same alert on your watch and phone, prompts you to take an ECG. Ideally, you should take an ECG reading as soon as you can. You may also want to take an ECG if you notice that your heart is beating irregularly. As mentioned, you can export your ECG readings and send them to your doctor. You can even play back a video of your ECG right in the app.
Importantly, the ScanWatch doesn’t detect heart attacks or other heart episodes. The app informs you multiple times that if you think you’re having a heart attack, you should seek medical attention.
In testing, I couldn’t consistently take an ECG reading. Out of every 10 attempts, I had to throw out roughly eight readings. Most of them were simply “too noisy,” while a few others failed midway through. Noise, in this context, can be anything from electrical interference to muscle movement or talking—anything that prevents a clear ECG reading from taking place.
I might have had better success if the instructions in the app better explained that I needed to touch the top metallic part of the watch’s case with my fingers to complete a circuit. Without that information, I didn’t know whether I needed to press firmly to get good contact between the rear of the watch (where there is another sensor) and my skin, or if there was some other purpose for holding the watch as shown in the instructions. A help page on Withings’ site shows a few dos and dont’s for positioning your hand while taking the ECG, though it still doesn’t explain clearly that you don’t need to place much pressure on the watch. I did eventually get the hang of it and was able to get more conclusive readings, but it’s still a finicky process.
SpO2 Testing Is Easier
SpO2 is an oxygen saturation reading that the ScanWatch and some other fitness trackers now offer. One very good reason to read your oxygen levels is if you have a respiratory illness, including COVID-19; a low score could indicate that you should seek medical attention. If you don’t own a finger-cup pulse oximeter, the standard tool for measuring blood oxygen saturation, the ScanWatch is a convenient alternative.
Optionally, the ScanWatch can take SpO2 readings throughout the night to detect disturbances in your breathing while you sleep. In addition, the app tracks deep and light sleep, as well as sleep interruptions. It doesn’t tell you about REM phases, however.
While these data points are somewhat advanced metrics, the only one feature that is unique to the ScanWatch is its breathing disturbance alert. Many other devices, such as the Garmin Venu and the Fitbit Charge 5, merely tell you if your oxygen saturation level dipped at any point during the night and highlight that data point on a graph. All of them convey the same information, but Withings draws your attention to it.
Just as with an ECG reading, you can take an oxygen saturation reading on the fly. The process is similar to taking an ECG, but, I had a much better success rate here in testing.
All-Day Fitness Tracking
The ScanWatch covers all the same metrics as other fitness devices, including step count, elevation, calories burned, sleep tracking, and so forth. It automatically tracks activities, too, such as when you’re running or swimming.
Like many other current fitness trackers, the ScanWatch also integrates breathing exercises. After you indicate how long you want to perform some slow inhales and exhales, slight vibrations and a visual indicator coach you through them.
I wore the ScanWatch simultaneously with a Garmin Venu Sq—similar to the Garmin Venu 2—to compare the step counts. The ScanWatch consistently reported significantly fewer steps per day and per walk (sometimes 20% fewer) compared with the Venu. It’s difficult to say which watch is more accurate, but I have high confidence in the Garmin device because I’ve worn it for several months without incident.
An Attractive Watch for a Niche Market
The Withings ScanWatch’s FDA-approved ECG feature is the main reason to purchase it. If you’re someone who might benefit from regular at-home ECG readings (and learn how to take the measurements correctly), then the ScanWatch can be legitimately useful. I’m not a doctor or medical expert, however, so you should consult your physician before buying the ScanWatch. Aside from the SpO2 and fitness-tracking capabilities, we also like the watch’s analog looks and long battery life. But given the somewhat finicky nature of taking ECG readings and the watch’s bulky design, the Apple Watch and the Fitbit Charge 5 are stronger alternatives. If you like Withings’ design language and don’t need to take ECG readings, meanwhile, you can save some money by opting for the older Withings Steel HR.
