A man looks at the internet site Foursquare June 21, in Washington, DC. Ranks of Foursquare users have continued to swell this year, with more than 10 million people sharing their locations with gadgets tapped into the service. - AFP Photo

SAN FRANCISCO: Ranks of Foursquare users have continued to swell this year, with more than 10 million people sharing their locations with gadgets tapped into the service.

The latest milestone came about five months after the New York City-based startup proudly announced it had topped six million registered users after growing at an impressive 3,400 percent last year.

Foursquare lets people log their locations by “checking in” from where they are at any given moment using smartphones or other Internet-linked devices.

Satellite location tracking capabilities of smartphones or mobile signal tower triangulation lets Foursquare estimate where members are when they check in.

People's whereabouts and text comments, if any, are then shared with selected circles of friends at Foursquare.

Foursquare rewards users with virtual “badges” for accomplishments such as traveling to distant places or frequenting boats or trains.

Some businesses have started offering deals to Foursquare users who check in on premises.

The service has logged check-ins from every country and one from an astronaut in space.

Foursquare commemorated the occasion on Tuesday with the release of an updated version of its application for Apple's popular iPhone smartphones that enable faster check-ins and an easier way to find local deals.