By now, you probably understand the overall architecture and atmosphere in which our app executes, but it won't be of much use without more services available at our disposal. Otherwise, with the limitation of pure Python code, we might have to bring everything that is required along with us to build the next killer web app.
To this end, Google App Engine provides many useful scalable services that you can utilize to build app. Some services address storage needs, others address the processing needs of an app, and yet, the other group caters to the communication needs. In a nutshell, the following services are at your disposal: