LAS VEGAS — Apple isn’t the only company blurring the line between medical device and smartwatch. I tried on Omron’s HeartGuide, a smartwatch that’s really a blood pressure cuff in disguise, on the CES show floor. After taking a measurement, I realized this watch could actually change lives.

A normal reading on Omron's HeartGuide smartwatch.

Unlike a blood pressure cuff, the HeartGuide is comfortable to wear, even as it tightened around my wrist to take a measurement. The process was simple: I pressed the top button on the watch’s case, then raised my arm across my chest, like I was about to recite the Pledge of Allegiance. The watch’s cuff tightened around my wrist for seven seconds; it felt similar to a standard blood pressure cuff when I go in for my annual physical, without the pinch-and-squeeze effect (maybe because my wrist is bony and my upper arm is decidedly not).

Like every good smartwatch, HeartGuide delivers notifications from your smartphone, tracks your steps and monitors your sleep. But underneath the polymer band is a medical-grade blood pressure cuff that can take a reading on demand. The watch has been cleared by the U.S. Food and Drug Administration to offer oscillometric blood pressure readings, and Omron’s Heart Advisor app analyzes the reading to tell you whether it’s low, normal or high. Soon, the app will offer personal coaching based on other factors, including your exercise routine and diet, that have an effect on blood pressure.

The watch gives you instructions before you begin a reading.

Omron recommends that HeartGuide owners take five readings a day: once in the morning, once at night and three other times to capture a range of measurements. You’ll be able to link your blood pressure to activity or emotion — your readings are normal after yoga, but high after a fight with your husband, for instance.

Eventually, HeartGuide will monitor your blood pressure while you sleep, which the company says is a more accurate predictor of cardiovascular issues. That functionality is already baked into the watch, but Omron is waiting for the FDA to clear the feature before it flips the switch.

Apple Watch Series 4, Withings Move ECG and other smartwatches offer (or are starting to offer) medical health features, but those tools are secondary to the watch part. With HeartGuide, it’s the other way around: This is a watch for people who don’t want to look like they’re constantly wearing a blood pressure monitor. (Bonus: HeartGuide can last a week on a charge when doing blood pressure readings, or a couple of days when used as an actual smartwatch.)

Omron plans to work with insurance companies, but it's currently conducting studies to prove its effectiveness at helping people manage their blood pressure.

I expected my reading to be normal, and it was. But where the elderly relatives in my life would never use an Apple Watch, even with its ECG app and fall detection, they could get a lot of use out of HeartGuide. Omron’s smartwatch definitely isn’t cool, but it doesn’t have to be. It’s one of the most practical gadgets I’ve ever seen at CES.