Facebook, Google and many other prominent companies host regular hackathons to encourage development of products not on the regular road map for the service’s evolution. By hosting its very own hackathon, Foursquare is encouraging developers to put their service to use in new and innovative ways.
The winning hack is The Dealio, which lets one Foursquare user leave messages for others at certain locations. For example, if I check-in to a Chinese restaurant at my neighborhood and find out that pot stickers are half off on weekdays at lunch, I could use The Dealio so that my friends see the tip the next time they check in to that restaurant.
FourGraph.me automatically generates an infographic based on your Foursquare user data, compiling and displaying total checkins, friends, following, tips, badges, how many people signed up before you, categories and more:
MakeThemPay.Me helps friends split a shared bill by connecting them on Foursquare and charging through Venmo, a mobile payments service. Venmo requires users to link a credit card and bank account to their phone (Android, BlackBerry or iPhone) to make payments to friends.
Agora, named after the open assembly area in ancient Greek states, connects Foursquare users that have similar interests based on their checkins and Twitter graph.
Finally, 4squareand7yearsago.com sends users a daily digest of old checkins, so you can see what you were doing on the same day exactly one year ago.