Shares of Fitbit (FIT) opened 52 percent above their IPO price on Thursday, putting it on track to rank among the top 10 stock market debuts of the year.
The stock opened on the New York Stock Exchange at $30.40.
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About 37 million shares of Fitbit had traded by 11:15 a.m EDT. For comparison, data storage firm Box (BOX) traded 42.6 million shares in its first full day of trading on Jan. 23.
The fitness wearables maker had priced its initial public offering at $20 a share on Wednesday, a day after it raised its IPO price range to $17 to $19.
The company is currently valued at $4.1 billion, and many investors will be eyeing its IPO since it is actually profitable.
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Fitbit CEO James Park told CNBC's "Squawk on the Street" ahead of the IPO that he believes his company can stay competitive even as Apple and other electronics makers ramp up marketing for all-purpose wearables like the Apple Watch.
"There's over $200 billion of consumer spending on health and fitness. This is a massive market. There's room for more than one dominant player," he said. "The brand Fitbit is really synonymous with health and fitness tracking, so we feel that we have really significant competitive differentiators in the market."
Investors should not be overly concerned that Fitbit will lose its first mover advantage in the next two years, said JMP Securities analyst Alex Gauna, noting that the Apple Watch had not "come out of the gates blazing."
"Apple is not in this market with comparable performance in terms of either price point, or integrated GPS, or battery life, so there's a lot of room for Fitbit to maneuver within the next couple of years," he said Thursday on CNBC's "Squawk on the Street."
Beyond the medium-term, Gauna said Fitbit faces significant challenges competing with the power that Apple can bring to bear in the battle over the Internet of Things, the emergent space for connected devices.
Fitbit is well-positioned because it integrates with both Apple's iOS and Google's Android mobile operating systems, but it must continue to innovate beyond its fairly narrow product range, Gauna added.
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Park said Fitbit cannot comment on details of its product pipeline, but he noted that research and development investment has doubled year over year, and the company will triple that spending to more than $150 million.
Fitbit has expanded into scales and electronics products that can be clipped to apparel. Park said services hold much potential.
"I think the next step is software, which really makes sense of the data to give you insights, coaching and guidance," Park said.
-CNBC's Kayla Tausche and Ari Levy contributed to this report.
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