Building a mobile app in the cloud using HTML5 and Ruby on Rails is a topic of discussion that will be covered at an event led by Carter Rabasa of Twilio and Chris Tosswell of Engine Yard, with technical demos to follow. The presentation will cover best practices for deployment, differences between smartphones and feature phones, key services and technologies, and how to scale faster with the cloud. For those interested in learning more about Ruby on Rails app development, Engine Yard provides a cloud platform that supports both small and large apps, while also offering related resources such as blog posts, videos, and documentation.