This document discusses building cloud-powered mobile apps using Amazon Web Services (AWS). It provides an overview of AWS services that can be used to build mobile backend functionality such as user authentication with Amazon Cognito, data storage with DynamoDB, media delivery with S3 and CloudFront, push notifications with SNS, and analytics tracking with Mobile Analytics. The document also discusses how the AWS Mobile SDK provides an integrated way to access these services and handles issues like intermittent network connections. Specific services are then discussed in more detail, including how Cognito can be used for user identity management and data synchronization across devices.