Are Fitbits and Jawbones competitive with the Apple Watch? What about the Microsoft Band, or Garmin products that act primarily as fitness devices but run third-party apps and show mobile notifications? Are these one and the same or completely, categorically different? That all depends partly on how you view the whole wearables market, but it's also simply a matter of how these companies are choosing to position their devices while more and more competitors pop up.

Take Fitbit. The San Francisco-based maker of popular wireless health and fitness products reported its third-quarter earnings earlier today. The company's revenue jumped 168 percent year over year, and it sold 4.8 million devices in the third quarter, up from 4.5 million sold in the previous quarter. At the same time, its stock dropped more than 7 percent after Fitbit said that key shareholders will be selling millions of shares. The TL;DR, then, is that consumers are still buying lots and lots of Fitbits, but even its rare-unicorn status as a tech company that actually makes money doesn't mean Fitbit is immune to stock market woes.

More interesting than its numbers are Fitbit's statements around Apple Watch, something that co-founder and CEO James Park has commented on before. The Apple Watch had "no material impact" on Fitbit's sales, Park said, according to The Guardian. He sees the products as catering to "very different segments in the market" in terms of use cases and price point.

Park's remarks are not too dissimilar from what Jawbone founder and CEO Hosain Rahman said at last month's Code Mobile conference in Half Moon Bay, California. "We think of the category in three different buckets," Rahman said.

"You have workout devices that are super accurate, for performance training. The smartwatch is a daytime use case, you don't wear it to sleep, it's for productivity, notifications, and some fitness stuff. And we think of ourselves as lifestyle — so you wear it all the time," Rahman concluded.

There is no doubt that some of these wrist wearables are very different from each other. A smartwatch with a relatively large display and one-day battery life that runs apps but can't claim any real health-tracking capabilities is different from, say, a dedicated workout band with a plethora of biometric sensors that lasts four to five days on a charge. Some activity trackers cost $50 or less; Misfit wearables come to mind. Some smartwatches cost several thousand dollars, or come with designer leather cuffs. Also, smartwatches are often tied to specific mobile platforms, whereas lightweight fitness trackers will often work with both iOS and Android (or Windows Phone).

But there are more wearables coming to market that borrow features from different devices, which means Fitbit's (and Jawbone's) categorical distinctions are super convenient for now, but won't necessarily be in the future.

Take for example the $249 Microsoft Band, which was recently reviewed on The Verge (and sparked a lot of discussion). It has impressive fitness-tracking capabilities and health software, but also borrows from smartwatches, with its large touchscreen display, third-party apps, and two-day battery life. Similarly, the $200 Garmin Vivoactive has all of the features you would expect with a Garmin, but it's a Garmin disguised as a smartwatch, with a color touchscreen display, the ability to show notifications and customizable apps and widgets. These are just a couple examples; the other, and most obvious, is Fitbit's own Fitbit Surge tracker.

Analysts and research groups repeatedly lump the different device types together. An IDC research report from earlier this year cited everything from Fitbits to Xiaomi activity-tracking bands to Apple Watch to Microsoft HoloLens in its predictions that the global wearables market would grow 173 percent in 2015.

Even Fitbit's CEO himself said in an interview around the company's IPO that there's likely to be more convergence in wearables. "One of the biggest misperceptions... is that you can try to split it," Park said in an interview with Recode. "I think over time there's going to be more blending. A lot of our own products have merged features, like caller ID or different form factors... and I think you'll see more of that."

So products like the Apple Watch or a Samsung Gear smartwatch may not have a material impact on activity-tracking wristbands, and vice versa — for now. But what happens if or when a new Apple Watch is made with GPS capabilities, or when a Fitbit workout watch runs third-party apps, or when a Garmin watch actually becomes stylish? What happens if Microsoft takes its Band and turns it into the smartwatch it kind of feels like it's meant to be? It will no longer be about the rhetoric of categorical distinction, but rather, what the best wearable device actually, truly, is.