SingTel's Amobee unit said on Tuesday it bought AdJitsu, which provides tools to make three-dimensional animated ads in mobile apps for iPhone and iPads. The acquisition of AdJitsu follows SingTel's purchase of mobile advertising company Amobee in March for $321 million.

The terms of the latest deal were not disclosed.

AdJitsu will be folded into Redwood City, California-based Amobee, according to both companies.

AdJitsu was a unit of Palo Alto, California-based startup Cooliris, which has raised $28 million from big venture capital names such as Kleiner Perkins Caufield & Byers, DAG Ventures and The Westly Group.

Cooliris Chief Executive Soujanya Bhumkar said mobile advertising is seeing a lot of activity with advertising networks and media content providers jostling to gain a foothold.

"The space is hot right now," Bhumkar said. "The numbers are actually insane in terms of both economics and engagement."

This year, U.S. mobile ad spending will grow 80 percent to $2.61 billion, according to research firm eMarketer. The market grew 89 percent last year to $1.45 billion in 2011, it said.

Even mobile handset makers are getting in the market. Samsung Electronics Co Ltd (005930.KS), which makes the Galaxy line of smartphones, last month announced its own mobile advertising service called AdHub Market.

In less than a year, AdJitsu had snagged major clients, including carmaker BMW and mobile handset maker Nokia.

Bhumkar said Cooliris sold AdJitsu - a business-to-business unit - to focus on its consumer-oriented divisions.

Cooliris started as a service to view photo and video content on the Web in a more visually appealing "3D Wall," but branched out to start AdJitsu and a photo-sharing app called Liveshare.

AdJitsu, which was spun off into a separate unit last December, has been receiving a lot of interest from both advertisers and ad networks, and growing at a rapid pace, Bhumkar said.

(Reporting by Poornima Gupta; editing by Edwin Chan, Jane Merriman, Steve Orlofsky and Andre Grenon)

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