This unofficial library in Ruby language supports the Foursquare Merchant API. It aims to facilitate new campaigns, specials, and venues. Instructions to use Ruby as a gem available as two single lines of code to choose from. Quickstart includes campaigns, specials, and venues. Created by Tim Olshansky.
The New York Times made news earlier this year through its release of several APIs (our Campaign Finance API Profile and our Movie Reviews API Profile). There's been promise of more APIs to come, and the latest prototype created by The New York Times gives a preview of what is to come.
The Transit App, an application that provides commuters with real-time transit information on iOS, makes its Transit App API available to developers who may want to integrate the functionality with other applications. The app has already been widely downloaded and received positive customer reviews, and filling the gap that was left when Apple removed transit from its own Maps app, it seems to be a really useful tool for anyone who relies on public transportation and the ability to get accurate and timely travel information.