Updated from 4:28 p.m. ET with comments from conference call

NEW YORK (

TheStreet

) --

Pandora

(P)

topped Wall Street expectations for its second-quarter results on Thursday, enjoying strong Web-based and mobile advertising revenue.

The stock gained nearly 4% to $12.95 in

recent after-hours action

, according to

Nasdaq.com

, with volume exceeding 500,000. Earlier in the extended session, the shares rose as high as $14.99.

However, the company was not able to completely shake investor fears about its inability to turn a profit, reporting a loss of 4 cents during its

first post-IPO earnings

.

Excluding items, the online radio company reported an adjusted profit of 2 cents per share on revenue of $67 million for its fiscal second quarter ended in July. Analysts had expected Pandora to break even on a per share basis on revenue of $60 million.

"Pandora is personalizing radio -- and consumers are enthusiastically embracing the dramatically better experience," said Pandora president and CEO Joe Kennedy said in a prepared statement.

Pandora's mobile advertising business comprised half of its revenue, a boon to the company which has faced concern about its ability to turn usage from iPhone listeners into ad sales.

The company, which went public at $16 per share, saw shares rise as much as 38% on the day of its IPO before they fell -- sharply.

Investor uncertainty about Pandora, compounded with extreme market volatility, has sent the stock

sliding 30% since its public-market debut

.

Pandora has faced skepticism about its ability to turn a profit as well as its power to fend off stiff competition from tech giants like

Amazon

(AMZN) - Get Report

and

Google

(GOOG) - Get Report

and upstarts like

Spotify

, all which are trying to gain market share in the online music space.

But the company believes there's plenty of room to grow, despite competition.

"We want to grow our listening hours and user base," Kennedy said during an earnings call with analysts. "We've penetrated less than 4% of the U.S. radio market."

Pandora has about 90 million registered users.

--

Written by Olivia Oran in New York

.

>To follow the writer on Twitter, go to

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