In this chapter, we've learned about testing and performance. In particular, we learned about the different kinds of testing with a special focus on unit testing. We first learned about unit testing without MVVM, and then learned how to do unit testing with MVVM Light. We then turned out attention to how to optimize ArcGIS Runtime's performance. In particular, we learned how to optimize ArcGIS Runtime's performance from the server side, and then we turned our attention to client-side performance considerations. Applying this knowledge and these techniques, we can make our apps as fast as possible.

In the next chapter, we'll conclude this book by learning how to build and deploy our app.