The wearble device market is exploding, according to new data from IDC.

In the fourth quarter of 2015, vendors shipped 27.4 million wearable devices, a 126.9 percent increase from the year before, the research firm said. For the full year, vendors shipped 78.1 million units, up "a strong" 171.6 percent from 2014.

"Triple-digit growth highlights growing interest in the wearables market from both end-users and vendors," Ramon Llamas, research manager for IDC's wearables team, said in a statement. "It shows that wearables are not just for the technophiles and early adopters; wearables can exist and are welcome in the mass market."

Wearables have not yet fully penetrated the mass market, meaning there's "still plenty of room for growth in multiple vectors: new vendors, form factors, applications, and use cases," Llamas added. "This will help propel the market further."

Plus, the wearable device market is more than just smartwatches and fitness bands.

"Though the top five certainly dominate with wrist-worn devices, there's been an immense amount of growth in other form factors like clothing, footwear, and eyewear — form factors that arguably require even more fashion sense than watches or bands," Jitesh Ubrani, senior research analyst for IDC mobile device trackers, said in a statement. 

Breaking it down by vendor, Fitbit ended 2015 as the "undisputed worldwide leader of wearable devices," — the same way it started the year — IDC said, with 29.5 percent market share during the fourth quarter. Apple came in second with 15 percent market share, but its shipment volumes for the period "grew only slightly" from the previous quarter.

"Expectations are higher for the next-generation [Apple] Watch," IDC said.

Meanwhile, No. 3 Xiaomi's inexpensive fitness trackers "resonated within China" during the fourth quarter, resulting in "the largest year-over-year improvement of any vendor" in the top five, IDC said. Rounding out the top five were Samsung with 4.9 percent market share and Garmin with 3.5 percent.

This article originally appeared on PCMag.com.