The Klarna-api-bundle PHP SDK by asgoodasnu is an SDK that integrates and wraps the Klarna API into a symfony2 bundle. The Klarna API allows developers to integrate Klarna's functionality with other applications. Some example API methods include emailing invoices, crediting invoices, calculating costs, and managing inventories.
Braintree, a web and mobile payments processing solutions provider, has just announced the launch of the Braintree Marketplace which enables customer payments to be split between a company marketplace and its sellers or providers. Developers can easily implement the brand new Marketplace payments solution using the Braintree API.
Xchangeonline is a tool that provides currency conversion and rounding functionality that can be integrated with other applications. Their selling point is that, unlike other currency conversion tools available, their service is easy for anyone to use, reliable and affordable. The Xchangeonline API makes it possible for third party developers to access this functionality.