Palo Alto-based Cooliris makes photo sharing and discovery apps for both Apple Inc's iPhones and smartphones that run Google's Android system.

Docomo's investment is the second from an international telecommunications giant for Cooliris. Deutsche Telekom previously invested through its venture arm T-Venture.

Large telecommunications carriers have been keeping track of new ways to share data and messages after seeing a steady decline in traditional text message usage, primarily as consumers moved to mobile apps that allow users to send messages for free.

"Asian carriers are currently the frontrunners in recognizing this need," Cooliris Chief Executive Soujanya Bhumkar said. "To account for this evolution in mobile habits, telco carriers are increasingly partnering with companies like us to keep them moving forward."

Bhumkar declined to reveal the size of the investment but said the company was coming out with redesigned photo sharing apps soon.

Representatives of Docomo, Japan's biggest mobile carrier, could not immediately be reached.

Cooliris has previously raised $28 million from big venture capital names such as Kleiner Perkins Caufield & Byers, DAG Ventures and The Westly Group.

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.

SingTel, which provides tools to make three-dimensional animated ads in mobile apps, bought AdJitsu last month.

Docomo has also backed Silicon Valley-based Internet-based note-taking application developer Evernote.

(Reporting By Poornima Gupta; Editing by Tim Dobbyn)

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