Shares of Fitbit. a maker of popular wearable fitness-tracking devices, shot up by as much as 60pc in their debut, valuing the company at $6.5bn (€5.7bn).
Fitbit is the second US wearable technology company to go public, following action camera-maker GoPro's hugely successful listing around this time last year.
Fitbit's colorful wireless wrist bands and clippable devices track heart rate, calories, sleeping patterns and step counts.
US President Barack Obama has been spotted wearing the Fitbit Surge watch, the highest selling GPS fitness watch in the United States in the first quarter of 2015.
The eight-year-old company had sold over 20.8m devices as of March 31, of which more than half were in 2014 as the wearable technology craze took off.
While Fitbit faces stiff competition from device makers such as Garmin, Jawbone and Misfit, its biggest challenger could be Apple's recently launched Apple Watch, due in Ireland later this year, which sports several health-related features and apps.
"Fitbit's success will be closely watched, just like the sales of the Apple watch, to really give investors a better sense of how viable and sustainable this market is," CLSA analyst Ed Maguire said.
About 126m wearable devices are expected to be shipped in 2019, representing nearly $28bn in revenue, according to IDC. In 2014, 19.6m units were shipped.
Fitbit said in its IPO filing it had an 85pc share in dollar terms of the US connected activity tracker market in the first quarter of 2015, citing data from NPD Group.
The company's revenue almost tripled to about $745m for the year ended December 31. (Reuters)