title: How do I implement continuous update of Google-Drive folder to a PHP app?
body: <p>I would like to implement a web-app with the following workflow:</p>
  
  <ol>
  <li>The user logs-in</li>
  <li>The user then selects one or multiple folders out of their Google-Drive</li>
  <li>From this moment on, the folder/s are synced on the server</li>
  <li>This happens continuously whether-or-not the user is actually on the application</li>
  </ol>
  
  <p>Please note the following:</p>
  
  <ol>
  <li>I'd much rather have this work on Google-Drive, but Dropbox or any other service will also do.</li>
  <li>I don't mind the user having to paste a 'Shared URL' for the folder rather than choosing, however, I would like to avoid CRON if at all possible.</li>
  </ol>
  
  <p>How do I go about it?
  Thanks in advance</p>