title: Using Firebase and S3
body: <p>I'm creating an app using firebase and ionic (Angular JS), and I would like to know if its possible to use amazon s3 to host photos, and store the url (from s3) in firebase, and serve it to the user. 
  I would like to do this because firebase can get pricy.</p>
  
  <ol>
  <li>Would this be an appropriate use of s3?</li>
  <li>Also when loading a file from s3 using its url, does this count as a request?</li>
  <li>If I use s3 for hosting only, where would the cost come from? Would I just be paying fore storage or are there other cost involved?</li>
  <li>Is this secure?</li>
  </ol>