Berlin start-up Readmill, is providing a platform for eBooks that connects readers regardless of what platform they are using. Readmill's core offering is a free bookreader that competes head to head with Amazon’s and Apple’s offerings. Unlike other eReaders, Readmill is based on a device-neutral, API-driven platform that integrates social recommendations, annotations and geolocation services.
The most popular Twitter ranking service, Klout, has used its API platform to boost its growth. The company, which is also expanding outside of Twitter, saw calls to its Klout API more than triple in just a few months. The company is now clearly in the API billionaires club.