The Rebel Mail User API allows you to send interactive emails from your application immediately. The emails work in all major clients including; iOS Mail, Apple Mail, Gmail, Yahoo, and Android. Rebel provides a way to make emails interactive while not requiring plug-ins and currently supports SendGrid, Mandrill, SailThru, Mailgun ESPs and more.
Eleven APIs have been added to the ProgrammableWeb directory in several categories including Tourism, Water, and Payments. One highlight today is the Continuum Connect API, which provides useful data for creating financial trading applications. Here's a rundown of the latest additions.