In this chapter we learned the importance of knowing how to debug Ext JS application and some tools that can help us with this task. We have also learned how to create test cases for Ext JS application using Siesta, an open source tool available in Lite and paid versions. We have also learned that performance is really important and we can do a lot more to improve the performance of our Ext JS application with the help of some free tools. And finally, we learned some tips of how to migrate an Ext JS application to a mobile platform and also where to find great plugins, extensions, and new components that we can use in our projects.
Now, it is time to let the creativity flow and create really awesome projects with Ext JS.