Foursquare acknowledged a grass-roots effort that started in Tampa, Florida [57] in 2010 by declaring April 16 ""Foursquare Day"",[58][59] April being the 4th month and the 16th being equal to four squared.[60][61] Some cities have made official proclamations of April 16 being Foursquare Day (Istanbul, Turkey; Atlanta, Georgia; Austin, Texas; Cincinnati, Ohio; Corpus Christi, Texas; Gaithersburg, Maryland; Indianapolis, Indiana; Kalamazoo, Michigan; Kennesaw, Georgia; Manchester, New Hampshire; New York City; Portsmouth, New Hampshire; Santo Domingo, Dominican Republic; Seattle, Washington; Miami, Florida; Victoria, Canada; Toronto, Canada; Ramat Hasharon, Israel; Singapore).[62][63][64][65]
Foursquare Day was coined by Nate Bonilla-Warford, an optometrist from Tampa, Florida on March 12, 2010. The idea came to him while ""thinking about new ways to promote his business"".[66]
In 2010 McDonald's launched a spring pilot program that took advantage of Foursquare Day. Foursquare users who checked into McDonald's restaurants on Foursquare Day were given the chance to win gift cards in 5 and 10 dollar increments. Mashable reported that there was a ""33% increase in foot traffic"" to McDonald's venues, as apparent in the increase in Foursquare check-ins.
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All details taken directly from provider content at http://en.wikipedia.org/wiki/Foursquare_Day