Tumblr announced the launch of mobile ads that will go into effect starting today and will be first time the social networking site is placing ads

After six years from its start-up, photo-sharing service website Tumblr has finally introduced the concept of mobile ads on its website. The company announced the these ads will look and feel like regular posts on the blog network.

Advertisers like GE, Warner Bros. and ABC will be the first among the lot to post their ads in the regular user stream, which, up until now, contained posts by people a user generally follows. iOS and Android apps users that use Tumblr on their mobiles will see up to four ads per day, and they'll be differentiated with a dollar-sign icon with beams shooting out of it, just as they are in the two existing placements. A Tumblr spokesperson said these ads will ultimately migrate to desktop computers but offered no timetable.

"We're incredibly proud of our partners' creativity and have been constantly amazed by how well these creations can fit into our Dashboards," Lee Brown, Tumblr's vice president of sales, said Monday in a blog post. "So today we're bringing these posts over to our mobile apps.

"This mobile advertising opportunity is native to how our consumers experience content on our apps; as a continuous stream," he said.

According to the statement, for the first week of the mobile ads, the premiere placements will belong to Warner Brothers, which will showcase teaser trailers for the upcoming films "The Great Gatsby" and "The Hangover: Part III," and GE, which will spotlight its jet engines and locomotives, Tumblr said.