At time when Facebook’s potential to generate revenue from its mobile platform is largely uncertain, one of the company’s social media contemporaries seems to be doing just fine with the mobile market. Twitter CEO Dick Costolo told a group at a conference in San Francisco this week that the micro-blogging site sometimes generated more revenue from its mobile services than it did from the web during the last financial quarter.

Costolo credited the success of Twitter’s mobile advertising strategy to the mobile-friendly design of the service. “We’re borne of mobile,” Costolo told the conference attendees when explaining the difference between Facebook and Twitter. “We have an ad platform that already is inherently suited to mobile, even though we launched our platform on the Web and only started running ads on mobile recently.”

Twitter amped up its advertising strategy earlier this year by introducing Promoted Tweets into the news stream of its mobile platform and on Twitter.com in addition to adding a Promoted Account feature.

So far, 2012’s been a year of milestones for Twitter. Last month, the site passed the marker for 6 million registered accounts and has as many as 140 million active users. Increasingly, and similar to Facebook, the majority of Twitter users are accessing the site via mobile device instead of the web.

Costolo’s been good for Twitter’s revenue growth since he took over in 2010. This year, the company is expected to pull in $269 million this year and that number could climb as high as $540 million by next year.