In the third spot sits Xiaomi. Despite selling nearly all of its Mi Bands in China, the company's 3.7 million devices sold in Q3 nabbed a 17 percent share of the global market. When you compare that to Q3 2014, Xiaomi's wearable business has grown 815 percent in the last 12 months. Garmin finished the quarter in fourth, thanks to its line of sports-focused devices and watches. Another Chinese company, XTC, debuted in the fifth spot on IDC's list, besting Samsung by 100,000 in sales. Like Xiaomi, XTC put must of its attention in China, releasing only one device. That wearable, the Y01, is a phone watch for children.

If Xiaomi is able to maintain its pace, and expand into other markets around the globe, it could give Apple a run for the number two position as soon as next quarter. It'll also be interesting to see if the holiday shopping rush and the Gear S2 can help Samsung return to the top 5.