Facebook develops ad tool to rival Foursquare.

Facebook has launched its long-awaited geo-location service, Facebook Places, as the battle for 'local' advertising revenues intensifies.

The service allows Facebook members to be 'geo-tagged' and share their location with friends. It is currently available only on Facebook for iPhones, but other mobile platforms are due to adopt the service soon.

The imminent UK launch of Facebook Places will pit the social networking site in direct competition with location-based social media app Foursquare, which is rapidly gaining traction with UK advertisers.

Facebook Places and Foursquare are widely seen as the next big thing in social networking, providing brands …