title: Get instance initialized with the new App Startup API
body: <p>I saw this new API in the Android dev guide,and I wanted to try it out since it looked like a really nice way to initialize components. But looking over the articles and the examples, it makes no sense to me how am I suppose to use this API. I get the first example, in order to use the <code>WorkManager</code> you would first need to call its <code>initialize</code> method, so this new API can handle that for you. But the <code>create</code> method of the <code>Initializer</code> returns an instance of whatever you are trying to initialize. This means that that instance is somewhere available for you to grab. But there is no explanation on how to retrieve that instance later in your code to use it.</p>
  
  <p>So my question is if there was anyone who got around to test this new API, if you could give me an example of how you use the instance that the App Startup API initialized for you. Thanks in advance!</p>