title: How to develop an app that has add-ons?
body: <p>Is there an outline or primer of how you would develop an app that has "add-ons"? </p>
  
  <p>E.g., how to develop some sort of framework for adding "themes" to an app?</p>
  
  <p>There is the basic app with 2 themes. The user should be able to download another app for a certain theme.</p>
  
  <p>How does the original app and the new downloaded app talk together? </p>
  
  <p>How would you develop the original app to get the theme information and graphic assets from the 2nd theme only app? </p>
  
  <p>My understanding is that apps are completely separate so this is why I am unclear how to accomplish this.</p>