The document summarizes the architecture of the Washington Post Social Reader Facebook app. It describes the growth of the app from 7 million users after 3 months to over 25 million users after 6 months. It then outlines the main components of the app's architecture including separate services for articles, social features, and interest analysis which retrieve and analyze data from various AWS services like S3, RDS, ElastiCache, SOLR, and EMR. The architecture also utilizes auto scaling, monitoring with CloudWatch, content delivery with CloudFront, and email services.