This is a post in ReadWriteBody, an ongoing series where ReadWrite covers networked fitness and the quantified self.

Most of the gadgets and apps I’ve tested for ReadWriteBody are geared towards fitness: getting healthier, not detecting illness.

That may be a result of the tech industry’s bias towards the fit getting fitter—the kind of insular thinking that led to venture capitalists passing over nutrition-tracking site MyFitnessPal until it got too big to ignore. We have too many devices and services for runners and gym rats, and not enough for moms and dads worried about sick kids or aging parents.

Scanadu, which ReadWrite recently named as one of 10 healthcare startups to watch this year, may have the answer.

A Different Device

The Scanadu Scout is different from most of the body-measuring devices I’ve seen so far. It’s a small, pocket-sized device that can read your body temperature, oxygen levels and heartbeat. An update will add EKG, EEG, and blood-pressure measurements.

It’s a scanner, not a tracker, inspired by the futuristic tricorder medical device in Gene Roddenberry’s Star Trek series. (No, seriously: It was an entrant in the recent Qualcomm-sponsored Tricorder X Prize contest.) It’s not yet in stores, but it’s getting closer, after a fundraising campaign on Indiegogo that put more than $1.6 million in the company’s coffers. De Brouwer hopes to sell it in pharmacies. (The final device will also be smaller than the beta version shown here.)

We tried it out at ReadWrite headquarters, with me as the test subject. The Scout works by holding up a metal plate to your temple, where it can pick up the widest range of vital signs. It doesn’t have its own display; instead, it connects to a smartphone.

You’ll no doubt be relieved to know that my signs came out normal. I tried exerting myself with a quick round of pushups, but I didn’t take into account my relative level of fitness. My heart rate didn’t spike noticeably. However, the Scout’s heart-rate readings closely matched those of the EB Sync Burn, a wrist-based fitness tracker I’ve been wearing.

An attempt to measure a boost in my heart rate from exercise failed.

I don’t think I’d carry the Scout with me all day. But that’s not the point. It really belongs at home, in the medicine cabinet.

“Our bet is on empathy,” De Brouwer told me. In other words, the Scout is for you to use on other people as much as on yourself.

To Boldly Go Where Fitness Trackers Can’t

Will the Scout replace the humble thermometer? At an anticipated price of $199, it’s unlikely to do so overnight. But it points the way to an area that other digital-health startups are ignoring: The interconnectedness of health.

Even the term we use for talking about analyzing the body’s data—”quantified self”—suggests a solipsism to be avoided. We care as much about the health of those around us as we do our own. (Sometimes, to our detriment, we care a bit more—caretakers famously neglect their own health.)

To realize its ambitions, I think Scanadu needs to do more than build a tricorder. It needs to connect the Scout to other apps and devices that track our exercise, nutrition and sleep. From there, it might begin to offer ideas of things to fix. But the notion that we can find out that something’s wrong with us by holding a gadget against our heads is itself something out of science fiction.

Scanadu's Walter De Brouwer tracks my vital signs on his smartphone.

Photos by Madeleine Weiss for ReadWrite

Update: Scanadu now says it expects to sell the Scout for $199, not $149. It will also measure blood pressure.