Vendors will ship 45.7 million wearable devices in 2015, up “a strong 133.4 per cent” from the 19.6 million units delivered in 2014, according to IDC.

The company noted factors including new vendors, new devices, and greater end-user awareness.

By 2019, total shipment volumes are forecast to reach 126.1 million units, resulting in a five-year compound annual growth rate of 45.1 per cent.

IDC splits the market into two categories: smart wearables, which are capable of running third-party apps (such as watches); and basic wearables, such as fitness bands.

The total volume of smart wearables in 2015 will reach 25.7 million units, up a “whopping 510.9 per cent” from the 4.2 million shipped in 2014.

Basic wearables will grow to 20.0 million units in 2015 from 15.4 million last year, resulting in 30 per cent year-over-year growth.

“The Apple Watch raises the profile of wearables in general and there are many vendors and devices that are eager to share the spotlight. Basic wearables, meanwhile, will not disappear. In fact, we anticipate continued growth here as many segments of the market seek out simple, single-use wearable devices,” said Ramon Llamas, research manager for the wearables team at IDC.

Wrist-worn wearables will account for more than 80 per cent of all wearable shipments throughout the forecasts – with most vendors having focused on this part of the body. This will be followed by “modular devices”, which can be worn on any part of the body with a clip or a strap – a category that is “simpler to produce than other wearable devices and function well as use-specific devices”.

Clothing is the third category, and is expected to grow the fastest as companies embedded computing power in items like shirts, socks, hats and other products. Eyewear is a “smaller category”, which will first catch on among enterprise users within “select vertical markets”.

Finally, “earwear” will comprise a small part of the overall market, as earphones gain health and fitness features.

“The explosion of wearable devices was clearly led by fitness bands, which until recently commanded prices that provided comfortable margins, but those days are changing. The price of these fitness bands have come down so significantly in some markets that smartphone OEMs are now bundling them with smartphones at little cost. Meanwhile, the market is quickly shifting toward higher-priced devices that offer greater functionality,” said Ryan Reith, program director with IDC’s quarterly device trackers.