In previous chapters, we walked through the design and creation of a series of applications in a formal manner, using a series of diagrams to illustrate the process. This time, I tried to give a glimpse of some of the ways I would build the system architecture and some of the techniques I use day-to-day.

In addition, we saw how a view model can become the primary point from which data flows through an application, cascading through child view models and child components, and triggering multiple UI updates via binding.

We revisited styling and showed how the Ext JS theming system allows you to build reusable mixins that give us the same modularity in our SASS code as we have in our JavaScript classes.

In the next chapter, we'll be writing a shopping application for tablet device that allows users to browse and buy items from an online store. It'll be our most complicated application yet, which marries all of the different ideas and techniques we've discussed so far.