Market researcher IDC recently tweaked its definition of wearable devices, which now includes wireless headphones that can activate smart assistants. Importantly, the change allows IDC to include one particularly popular product: Apple's (NASDAQ:AAPL) AirPods. After taking the adjustment into account, the researcher now estimates that worldwide wearable device shipments in 2019 will jump 15% to 198.5 million. Smartwatches, earwear, and wristbands are expected to drive unit volumes this year.

Here's what the estimates mean for companies competing in the wearables market.

People playing basketball while wearing Apple Watch

Image source: Apple.

Approaching 200 million

IDC breaks down its latest forecast by category instead of by vendor. Companies are now exploring connected clothing, but that category is expected to pale in comparison to smartwatches, earwear, and wristbands.

Product Category

2019 Estimated Shipments

2019 Estimated Market Share


90.6 million



54.4 million



49 million



3 million



1.7 million



198.5 million


Data source: IDC.

Smartwatches representing the bulk of wearables volume bodes well for Apple and Fitbit (NYSE:FIT), currently the two leaders in the smartwatch space. Fitbit recently introduced an even more affordable version of its popular Versa smartwatch called the Versa Lite, which should help it cement its place as No. 2 behind Apple. Competition could soon start to chip away at Apple's position, though, with watchOS only expected to represent 28% of the smartwatch market by 2023, according to IDC's forecast.

In terms of the next-biggest category, earwear volumes could hit nearly 55 million this year as smart earbuds continue to grow in popularity. Samsung just released its Galaxy Buds, which support both Google Assistant and its own Bixby, to compete with AirPods. Adding biometric sensors -- which Apple is potentially doing with AirPods 2 based on patent filings -- will also help drive demand going forward, IDC believes. Fitbit's Flyer wireless headphones don't appear to qualify as wearables based on IDC's definition, since they lack any type of biometric sensors and don't provide access to virtual assistants.

Check out the latest earnings call transcript for Apple.

Once upon a time, wristbands like basic fitness trackers represented the bulk of the wearables market, but consumers have been shifting toward more full-featured devices in recent years. The category is still popular in certain regions but isn't expected to grow much in the years ahead. IDC expects China's Xiaomi and Huawei to continue owning this segment of the market, although basic trackers still represented over half of Fitbit's revenue in 2018.

Connected clothing is still a nascent category, mostly comprised of things like step-counting shoes. IDC notes that connected clothing is starting to take off in China, but Nike and Under Armour are starting to ramp up their efforts. For example, Nike introduced connected jerseys for professional sports teams in 2017 and recently launched self-lacing shoes similar to the ones imagined in Back to the Future II. Under Armour has also been developing connected clothing for a few years now.

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