"We are going to compete on simplicity," Costolo said Monday in an onstage interview with John Battelle at Web 2.0 Summit, which is produced by Battelle's Federated Media and O'Reilly Media in partnership with UBM TechWeb.
Costolo took over as CEO from Twitter co-founder Evan Williams in October 2010. Costolo was instrumental in the creation of the promoted Tweets ad format, which he now says has worked "better than we even hoped, to tell you the truth." Twitter will experiment with other ad formats but wants to make sure they are delivered as a natural extension of the service, he said.
Even with that focus on simplicity, however, Costolo acknowledged Twitter needs to work on lowering the learning curve for the service and boosting engagement.
Still, Twitter is not even trying to build the same kind of social network as Facebook or Google+, Costolo said. "We think social only in the context of delivering the most relevant information to you right now."
[Get more news and videos from Web 2.0 Summit.]
Twitter is experimenting with new search mechanisms to improve relevancy, but wants to do so without ruining the things fans of the service like most about it. Paraphrasing a quote from science fiction writer and technology prognosticator William Gibson, he said Twitter needs to continue to deliver "the voice of the street." (Gibson said that in contrast Facebook was more "like a mall.")
"We've got to figure out how to capture all the volume and at the same time separate out the signal from the noise," Costolo said.
Similarly, when Battelle asked whether it was wise for Twitter to be "tying part of your future to Apple's wagon" through Twitter integration with Apple's iOS 5 mobile operating system, Costolo said the partnership made perfect sense because of Apple's focus on simplification.
"We are adding simplicity in a world of complexity. It's really hard to edit things out," he said, because engineers are always looking to add things. "They've been a corporate mentor to us in that respect, and a great partner."
The integration is also driving five times more signups by iOS users, Costolo said. Overall, Twitter now has 100 million active users, half of whom sign in at least once a day, he said.
Most companies have little control over their heaps of unstructured data, our research reveals. It's time for a content management strategy. Get the new, all-digital InformationWeek supplement. Download it now. (Free with registration.)