This document discusses the evolution of applications from desktop apps to web apps to mobile apps to messaging apps. It then focuses on bots as the future of apps, explaining how bots can be built using various platforms' APIs and deployed. Key points covered include how bots are similar to users in messaging apps, how they can be rules-based or AI-based, basic bot architecture, registering a bot, creating bot services, testing bots, deploying bots on Azure, and including attachments in messages.