title: Android: upload files totally in background
body: <p>I have to create a multiple file uploads (3-7 photos), but this upload must be totally managed by the system, so that, even if the user closes the app, it should work until it completes uploading.</p>
  
  <p>A little like Facebook, it upload a photo and if the app is killed: the progress also appears in the notification bar.</p>
  
  <p>I currently use a class, I think FtpClient, which works well but if I close the app it stops. Everything is asynchronous but only for the app, not for the system.</p>
  
  <p>How can I do that?</p>