Wearables Are Here To Stay

From smart watches to health monitors and fitness trackers, wearable devices are on the cusp of big growth and will appear on two out of five internet users within the next four years, eMarketer reports.

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Nearly 40 million American adults are already wearing the devices today—that number will nearly double by 2018 and rise even higher. (A wearable is an accessory or piece of clothing that is embedded with internet-connected electronics and that can exchange data with a manufacturer or another electronic device.)

eMarketer wearable user chart

A 2014 survey from North American Consumer Technographics showed that consumers are interested in all kinds of wearables, but that watches seem to have the most popularity:

North American Consumer Technographics Wearables Survey

Who's sporting wearables?

Wearable devices are already trending among Americans between 25 to 44 years old. This demographic includes those who are most involved in tracking their data and fitness activity, according to eMarketer. An interest in health could also be a potential a draw for older users: They are undoubtedly more likely to be concerned with monitoring their health.

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Wearables could be the next big thing to reduce healthcare costs and revolutionize preventative medicine, according to a study from Technology Advice. If patient-generated data can be directly synced with electronic medical records, doctors can monitor patient activities — such as a patient's step count or heart rate — and record health trends and abnormalities without actually seeing patients, a source for the study says.

Tech review company CNET ranked the Apple Watch and various fitness trackers such as the Garmin Forerunner 225 and Jawbone Up2 as the best wearable devices in 2015.

Wearables are also evolving into fashion items, moving beyond a purely utilitarian design. Consider the Opening Ceremony MICA luxury bracelet, which was featured at New York Fashion Week.

Opening Ceremony MICA luxury bracelet

It features 18-karat gold details and real snakeskin. The 3G-connected bracelet can display notifications from your phone and has a 48-hour battery life. (Retail price is $495.)

Other stylish wearables include the following:

Motorola's Moto 360 2

Moto 360 2 smartwatch

The Android Wear watch from Fossil: Fossil Q

Fossil Q smartwatch

The main obstacle to the new technology is persuading digital advertisers to invest in them, generating revenue for wearable companies.

"The consensus among the experts that we consulted is that advertising will not appear in volume on wearables until one or more of the devices attains significant [audience] share," eMarketer senior analyst Cathy Boyle said. "Which makes sense, considering that scale is a critical aspect of digital advertising."

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