You have now gained experience with the techniques to build HTML5 screens with input fields that know how to validate data, further controlling data through Dart and storing them in the browser's local storage for offline use. This is not a replacement for server side validation: data sent from a client should still be validated on the server.

Along the way, we perfected our skills to work with JSON, and learned how to (de) construct Dart objects to/from JSON. All these can be used at the front-end of your business application. If you need a more complex user interface, web components are the way to go. We will explore them in detail in Chapter 8, Developing Business Applications with Polymer Web Components. In the next chapter, we will sharpen our modeling and game building skills, adding multimedia functionality to our applications.