Poggled
The Poggled app uses a web service to bring deals from the Poggled website to the iPhone. Poggled is a Chicago-based deal provider that offers coupons related to nightlife, including drink and cover-charge specials.
I was the original developer of the Poggled iOS app. As a user, you can perform location-based searching for deals in your area sorted by distance. You can also filter your searches by neighborhood, by day of week that the deal is offered, by bar or deal location, and more. If you find a deal that you want to buy, you will be required to login or register before proceeding. You can do classic registration or you can login using your Facebook account via Single Sign On. Logged in users can purchase and redeem deals from within the app.
