> When someone checks in to a place on Swarm, Foursquare's newer app, the company records the user's coordinates, helping it determine all the different coordinates associated with a single business or other place.
> Foursquare says it can't disclose who its partners are, or how many different smartphone users' data it has acquired. But Rosenblatt says the company could, for example, create a list of "millions" of smartphone owners who frequently visit fast food restaurants by taking a pool of location data collected by its partners and comparing that to its database of fast food restaurant coordinates.
> Advertisers could then use that data to show those users ads for fast food chains, or perhaps healthier alternatives or gym memberships—all without those people ever having to install a Foursquare app.
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