There are over 20 million people in the Foursquare community
When you use Foursquare for business, your customers can check-in and search for deals. Nearby specials are highly visible to users. Businesses have the ability to create specials on Foursquare as a free way to find new customers and engage current ones.
You can give away free items, discounts with a purchase, special treatment or a free item after a certain number of visits.