Facebook's app for the Apple Watch. Source: Apple Keynote

The first round of Apple (AAPL -0.57%) Watch reviews hit the Internet last week, and the consensus is largely positive. Even if the device isn't perfect, many expect it to sell exceptionally well compared to other smartwatches. What's more, the success of the Apple Watch would likely give a boost to the entire smartwatch industry -- just as the iPhone did for smartphones and iPad did for tablets.

While smartwatches are designed to complement smartphones, they create value in reducing the amount of time you have to interact with the technology on your person. That means companies that create value from users spending time on their platforms -- like Facebook (META 1.54%), Twitter (TWTR), and Google (GOOG 0.37%) (GOOGL 0.35%) -- could see a negative impact from the Apple Watch and the potential popularity of the general smartwatch category that stems from it.

How the Apple Watch aims to change behavior
If a person wants to browse his or her Facebook News Feed or Twitter Timeline, they're probably not going to do it on their Apple Watch. The Facebook and Twitter apps for Apple Watch are largely designed to provide little snippets and alerts of pertinent information like friend requests or @ mentions. While the Twitter app allows users to browse their Timeline, if people want to get the full experience of these apps they'll likely want to get their phone out.

Ultimately, that means the smartwatch is adding marginal utility to these apps. That might change, of course, as Facebook and Twitter adapt to the new platform just as they did for mobile. But adding utility on the smartwatch isn't necessarily in their best interest. The smaller screen makes for less room for advertisements and the glancing interactions make for less time to display them.

Right now, the limited utility isn't a problem, but it could become one down the road. If other apps find ways to engage users on smartwatches, they could pre-empt users from checking Facebook or Twitter on their smartphone as much. Consider that Snapchat's photo and video messaging platform extends well to the watch (press and hold the crown) and Facebook and Twitter may find themselves overtaken by a new round of apps designed for the smartwatch first.

Voice control
The watch is also focused on speech recognition as a means of input. If people really do become used to talking to their wrists, it could increase the amount people use Siri for cursory Web searches. Siri on Apple Watch is a lot easier than on iPhone, in that users just have to say, "Hey Siri" to activate the digital assistant. This functionality is only available in the iPhone when it's plugged in.

It's a feature that Google integrated into Android, allowing users to say "OK Google" to start a search. Google also has voice search in its smartphone app. For simple searches, the Apple Watch could impact the amount Apple consumers use Google's search engine because Siri is powered by Bing.

Of course, that's not a big problem for Android Wear smartwatches, but Google has faced some pushback from major OEMs over Android Wear. Refusing to open up its operating system a bit more for hardware manufacturers to tinker with could negatively impact Google's search business on mobile.

What to "watch" for
As the popularity of smartwatches increases with the launch of the Apple Watch, investors in companies like Facebook, Twitter, and Google should watch to see if they're able to adapt to how people use the watch with relation to their smartphones. Facebook and Google were notoriously slow to adapt to the shift to mobile devices. Facebook has recovered well after a rocky start, but it's now a publicly traded company, and some investors aren't very patient. Google's experience with mobile hasn't gone as well, but it's adjusting along with expectations.

At the very least, investors should listen for commentary from management about the problems smartwatches present for their businesses, and the potential solutions they have in mind.