SAN FRANCISCO » Apple has bought Topsy Labs in a deal that will provide the iPhone maker with more insights about the chatter on Twitter.

Topsy pores through the stream of conversations occurring on Twitter to identify trends and people influencing public opinion. The San Francisco startup also runs a free search engine that boasts an index of every tweet posted since 2006, a resource that’s not publicly available on Twitter’s own online messaging service.

Apple Inc. spokeswoman Kristin Huguet confirmed the Topsy acquisition Monday without elaborating on the Cupertino, Calif., company’s plans for the Twitter analytic tools. The acquisition price wasn’t disclosed.

"Apple buys smaller technology companies from time to time, and we generally do not discuss our purpose or plans," Huguet said.

Getting a better grasp on the hottest topics on Twitter could help Apple sell more advertising on iPhones and iPads.

Apple has been trying to boost its mobile advertising revenue for years.

Topsy’s Twitter tools also could be used simply to give the iPhone a search feature that isn’t available on rival products running on Google’s Android operating system. Unlike Topsy, Google hasn’t been able to obtain a licensing agreement that would give its search engine more immediate and deeper access to Twitter’s content.

Twitter ranks among the most popular applications on smartphones, so a quicker way to search through tweets on the device might appeal to some consumers.

Apple spent a total of $496 million acquiring other companies during its last fiscal year ending Sept. 28. In comparison, Google Inc. spent $1.4 billion acquiring other companies during the same stretch.