OK, so that's great progress for now. We can now add todo items to our app, and the state of the data is Tracked using our service. Next we'll move on to getting our footer functionality working, including the todo counter, and look at conditional rendering, including correctly styling todos when they've been checked. We'll also wire up our "Clear completed" button....setting up a service to keep track of the data state of our app...control interactivity, and keep track of app state using a service...