The Postmark PHP SDK by Wildbit allows API interaction with the aim to simplify email communication. References include guides for installation and API calls. A sample displays how to send a first email from the app.
As a developer, you can figure out how to make your program connect to Facebook, Twitter, SMS, and Email. Or you can use the Embarke API and connect just to Embarke, a messaging platform that connects you to them all. You can skip learning the specifics of how to connect to each of them. The REST API's website has a five minute tutorial video on how to use this gateway to its developer tools for social communications.