API Gateway does a number of things. It distributes endpoints via cloudfront, which is pretty awesome. It serves as a unified front end for a collection of back

API Gateway does a number of things. It distributes endpoints via cloudfront, which is pretty awesome. It serves as a unified front end for a collection of back end microservices. It handles client cert authentication (important to us, but not to most people) and api keys for you, and a bunch of other neat stuff as well. And it offers a test harness where you can mock up data easily. In theory, you could do the same thing with nginx and load balancers and multiple ec2 instances, but it'd be a lot more work. And I think the real magic is with integration with Lambda. That's a game-changer.