The Build 2014 conference was recently held in San Francisco. See http://www.buildwindows.com/ for links to all the key note and session videos.
Our very own Beth Massi gave a talk about Cloud Business Apps. In her session she builds a survey application from beginning to end. This includes the design of the data, integrating with SAP, modifying the UI using CSS, integrating with a SharePoint newsfeed and publishing the application. The overall all architecture of Cloud Business Apps is shown as well.
Check it out: Developing Office 365 Cloud Business Apps