AWS Lambda now supports Synchronous Invoke for scalable mobile back ends(aws.amazon.com)
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AWS Lambda now supports Synchronous Invoke for scalable mobile back ends
http://aws.amazon.com/blogs/aws/aws-lambda-update-production-status-and-a-focus-on-mobile-apps/
Now with Synchronous Invoke you can have a backend for a mobile app live fully on AWS Lambda. The benefit being you pay by the millisecond for compute time used vs having to keep EC2 nodes up and paying for underutilized instances.