Button, which brings services and apps together, has announced the Button Marketplace. The shop lets developers quickly identify services (buttons!) they want to add to an app, and the API or SDK code to make it possible.
If you’re not familiar with Button, it’s best described as plug-ins for apps that let you do things like make reservations or hail an Uber. Foursquare recently made good use of Button in an app update, which allows users to reserve a table at a restaurant via OpenTable from within the Foursquare app proper.