The document discusses the evolution of web application architecture over the past decade. It describes how architectures have transitioned from server-side HTML composition to client-side single page applications powered by RESTful APIs and JavaScript. It also outlines the main challenges of mobile and touchscreen devices, including smaller screens, poor network connections, and user expectations of dedicated apps. Solutions discussed include responsive design, techniques for improving performance over slow networks, and moving application logic and data access to the client side.