title: HTML5 File API downloading file from server and saving it in sandbox
body: <p>I'm trying to understand HTML5 API.
  I'm designing the web application where the browser client need to download multiple files from server; user will perform something with the downloaded files and the application than need to save the state on user hard-rive. I understand that the browser can save these files only to its sandbox which is fine as long as the user can retrieve those files on the second time he starts the application.
  Should  I use BlobBuilder or FileSaver? I'm a bit lost here.</p>