Total shipment volume for the quarter was 18.1m, up 223.2% from the 5.6 million units shipped in 2Q14.

IDC’s report Worldwide Quarterly Wearable Device Tracker, shows that Apple’s arrival had the greatest impact on the smart wearables category, or those devices capable of running third party applications.

Ramon Llamas, research manager for IDC’s Wearables team said: “Anytime Apple enters a new market, not only does it draw attention to itself, but to the market as a whole. Its participation benefits multiple players and platforms within the wearables ecosystem, and ultimately drives total volumes higher.

“Apple also forces other vendors – especially those that have been part of this market for multiple quarters – to re-evaluate their products and experiences. Fairly or not, Apple will become the stick against which other wearables are measured, and competing vendors need to stay current or ahead of Apple,” he said.

Currently about two of every three smart wearables shipped this quarter was an Apple Watch, and IDC’s analysts caution that although Fitbit out-shipped Apple, Fitbit only sells basic wearables and this is a category that is expected to lose share over the next few years.

Fitbit has a market share of 24% compared with Apple’s 20%, Xiaomi 17%, Garmin 4% and Samsung 3% in Q2 2015.