Alex builds/maintains a Mobile Checkout app (at FutureProofRetail.com), which like Uber/Lyft and other popular ride-sharing apps, involves a tight coordination between server state and app state. This kind of app is very difficult to build and test with confidence, and Alex presented on the current state of design patterns and best practices to facilitate building such an app. Alex touched on Uber's open-sourced RIBs architecture, as well as what we've built in Ember to make it easier to build these kinds of apps. Alex believes this talk will be of interest to anyone who's tried to build an app with a live socket connection to the server (e.g. WebSockets), which is probably most people at this point :).