Wearable tech shipments grew 197.6 per cent year on year in Q3 2014 to 21m units, according to IDC – and Chinese manufacturer Xiaomi is threatening to overtake Apples position.

While Fitbit continued to hold the top spot, with the number of shipped units doubling year-on-year to 4.7m, its market share shrunk to 22.2 per cent in the face of increasingly strong competition.

Having debuted as the second biggest vendor the previous quarter, following the launch of the Apple Watch, Apple shipped 3.9m units in Q3.

Apples market share of 18.6 per cent was enough to maintain the second spot, but Xiaomi was hot on its tail, with 3.7 units shipped – up 815 per cent year-on-year – and a market share of 17.4 per cent. This rise was driven by the low-cost Mi Band, especially in China, which accounted for 97 per cent of shipment volume.

All other competitors were left in the dust, with Garmin a distant fourth with 0.9m units shipped.

“The early stages of the wearables market have led to tight competition among the leading vendors, and Chinese vendors have seized upon market momentum to grab market share,” said IDC wearables research manager Ramon Llamas. “China has quickly emerged as the fastest-growing wearables market, attracting companies eager to compete on price and feature sets. In addition, multiple vendors have experimented with a broad range of products and applications. The challenge, however, is whether these vendors can expand their presence, as few have extended beyond the countrys borders and into other markets.”