Stymied for the time being in its effort to acquire DoubleClick for $3.1 billion, Google is having more success buying up small companies.

Mobile social networking service Zingku said Thursday that certain of its assets have been acquired by Google for an undisclosed sum. This marks the 11th company Google has purchased since it announced its intention to buy DoubleClick in April, and the 15th company Google has targeted this year.

"We've entered into an agreement to have Google acquire our Zingku service," Zingku said on its Web site, noting that new user accounts are now frozen.

"We acquired certain assets and technology of Zingku," a Google spokesperson said via e-mail. "We believe these assets can help build products and features that will benefit our users, advertisers and publishers. Aside from this, we have no other plans to announce at this time."

Zingku is a service designed to make it easier to share content with friends using a mobile phone and the Zingku Web site. "Our service integrates your mobile phone with a personalized Web site so that you can easily move (zing) things back and forth between the Web and your mobile, as well as powerfully connect with friends and optionally their friends," the company explains on its Web site.

The fact that Zingku is a mobile phone service lends further weight to reports that Google plans to bolster its presence in the mobile phone sector, potentially with the release of its own handset.

Some of the content that Zingku expects its users to share is advertising. "Merchants create 'mobile flyers' and then publish/email a 'zing-code' to their customers who opt to pull the flyer to their mobile phone," the company said. "The customer can then zing it to those friends who they think may be interested."

If Zingku takes off, it may not be long before this form of viral advertising drives someone to create Friend Blocking software.