Until recently, only a handful of vendors have had access to the Facebook Ads API—a few major tool developers and some folks willing to make a $5M deposit with Facebook. We've been running Facebook ads and building apps for the last 4 years. The breakdown on the Facebook Ads API: It’s not exactly as robust as the Google AdWords API, but that creates an opportunity to build what Facebook has missed, or game the system, depending on whether you’re white or black hat.
Rebelmail publicly launched its interactive email API. After successful private integrations with ESPs like Mailjet, SendGrid, and others; Rebelmail is ready for third party integrations across the board. Through the API, users can build, send, and track interactive emails directly within an app.