The answer is that your component doesn't have a listener to be notified of an update. What you need to understand is that react updates components in 2 situations :
Your component `App` right now neither update the store or receive different props.
Here is what is happening to your application right now :
You actually got close to the answer by calling `store.subscribe` ! I suggest you think a bit more by calling it into your component `App`, and do some stuff there and see if you can find out a way to notify `App` that your store has changed, so it need to re-render.
I also suggest you, once you're familiar with that design pattern to take a look at react-redux, which is the way most people bind their Redux store to their react application right now. It'll basically do all the work you need to do right now for you !
Keep up !