HELSINKI (Reuters) - Nokia , the world's largest cellphone maker, started to roll-out its online gaming service N-Gage on Tuesday as it expands into mobile Internet services.

Nokia also opened its social networking site "Share on Ovi" on Tuesday, which allows people to share photos and videos and is built on technology acquired with the U.S. firm Twango, a spokesman for the company said.

The gaming service and the media sharing site are among the cornerstones of Nokia's big push into mobile services under its new "Ovi" brand.

Nokia is the first handset maker to move strongly into the content space with services like music or filing sharing site Mosh, where millions have downloaded audio or video files, programs or documents.

Nokia delayed the gaming service twice last year due to delays in software testing and starts to roll out to owners of its N81 multimedia phones around the world.

"It's the most gaming-optimized device," said Nokia spokesman Damian Stathonikos.

(Reporting by Tarmo Virki; editing by Kim Coghill)
© Copyright 2007 Reuters.