Facebook's mobile usage has tripled this year to 65 million

How addictive is Facebook?

The company, which is often tight-lipped about its numbers, revealed a bit more about its user engagement today at the Nokia World conference in Stuttgart, Germany.

About half of its 250 million monthly users worldwide log in every day. About a quarter, or 65 million, used the site from mobile devices in August, according to Henri Moissinac, director of Facebook Mobile. That’s more than three times what it was in December, when 20 million users were using Facebook through apps and the company’s mobile web page. The U.S., U.K., Canada and Indonesia have the most active users.

Those could be nice, sticky numbers for advertisers, who are looking to see traffic and attentiveness if they’re going to run large brand campaigns on the site. Intensive mobile usage and sharing would also be a plus, giving Facebook the edge if it wants to deliver location or time-sensitive ads based on people’s habits.

The social networking site is trying to tighten its partnerships across all platforms. Nokia and Facebook announced a lifecasting app, that would make it easier for users to send status updates and their locations on the N97 and N97 mini Nokia models.

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