ReadWriteBody is an ongoing series in which ReadWrite covers networked fitness and the quantified self.

It’s as if no one at Apple has ever gone jogging before. Launched to much fanfare this week, Apple’s new watch proclaims itself a jack of all trades, doing everything from showing text message alerts to sending your doodles or heartbeat to that special someone. The one thing it can’t do, despite calling itself a “sport” watch? Keep track of your exercise.

See also: The New Apple Watch Leaves Fitness Trackers Looking Unhealthy

A bit of a glaring omission, no?

The One Essential Feature

Not that Apple needed to do this. Enough people will want to check their email from their wrist (because, well, it’s hard to glance at that phone!) that Apple will likely sell plenty of über-watches.

But no, Apple chose to target the fitness crowd, and it did so without the one feature that matters more than any other: GPS.

Sure, there’s plenty of exercise that doesn’t require serious lateral or forward movement, and Owen Thomas captures the several uses fitness buffs can get from the new watch. Exercise bicycles, treadmills, jump ropes and more all let you get a good workout without moving around. But for many of these more-or-less stationary exercises, the fitness equipment itself is tracking distance and, sometimes, heart rate.

But exercise that doesn’t take place indoors—you know, the exercise for which we happily spend several hundred dollars to buy a (GPS-enabled) Garmin watch—requires GPS if you’re going to really track it.

See also: What You Can Do With An Apple Watch

About the best thing you can do without GPS is make out, as these runners are doing. The Apple Watch Sport is capturing their elevated heart rate, but that’s about it:

My Enthusiasm … Deflated

Don’t get me wrong. There are things about the Apple Watch Sport that I love. I often carry an iPod Nano with me when I run. The Watch Sport means I can carry my music with me on my wrist. So that’s a plus. It also means I can ditch the heart rate strap that I normally wear when I run or bike, which is another plus.

That’s why my initial response to the Watch Sport was positive:

Wasn't impressed with the iWatch but…music while exercising and a replacement for my Garmin to track speed/calories? OK. I'm in. — Matt Asay (@mjasay) September 10, 2014

But none of the aforementioned features adds up to the $349 (at a minimum! Apple hasn’t been at all clear on pricing) I’d need to spend on the Apple Watch Sport. The only thing that has justified that amount of money for me is GPS. It’s the ability to track distance—to measure how well I’m doing on a run—that has convinced me to buy several Garmin devices over the past few years.

And, no, it’s a not acceptable to lug around my iPhone with me, especially now that they’re getting even bigger (even if they are lighter). That defeats the entire purpose of having a dedicated exercise device.

Besides, in my experience carrying my iPhone with me on long bike rides, its GPS works nowhere near as well as my Garmin Edge 500. I’ve used both simultaneously on rides up the Alpine Loop at Sundance, Utah, and my Garmin kept perfect track of distance while my iPhone’s GPS crapped out repeatedly.

No GPS, No Deal

Apple has built what looks like a decent watch, one that apparently does all sorts of nifty things. But it has built a terrible exercise watch, and has made it worse by advertising it expressly as a “sport watch.” That’s false advertising, given that it can’t provide the most essential fitness technology: GPS.

Yes, I’m sure the next generation watches will have GPS built-in, once the cost and battery issues are resolved. But for now, I’m sitting this Watch Sport out, even as I enthusiastically wait in line to buy the iPhone 6.

Photos courtesy of Apple