The Apigility PHP Library assists in the creation of APIs using agile methodologies. It is available in JSON architecture in RESTful format, using OAuth2 and HTTP to authenticate. Agility can be downloaded in any Linux, PC, Apple, or PHP related computing system.
Unless you've tried to make a sports app, you might not realize how hard it is to get data about sports. And most sports are full of data about possession, assists and other sporty attributes. The Sports Data API aims to make it more available, at prices that should allow more apps to be able to afford including the data.
Gravatar is an attempt to allow users to have one globally recognized avatar. The service, around for several years, allows a user can set an image as an avatar and have it recognized on a variety of sites. Later, users can change an avatar once and have it change on every Gravatar-enabled site that they use. Though the service is somewhat well known, what is not is its robust API for developers to integrate the Gravatar service into their own sites.