This document provides an overview of using Google App Engine as a Platform as a Service (PaaS) for PHP applications. It discusses downloading the Google App Engine SDK for PHP, using Composer for local development, installing the Silex micro framework, signing up for a Google account, and deploying a PHP application to Google App Engine either via the project launcher or using Git push. Maintenance of the application includes committing and pushing code changes and changing the version number in the app.yaml file.