Whenever you first use Dropbox in OnSong, you will need to first authorize OnSong to access your Dropbox contents. This is handled completely by the Dropbox SDK, so no information is passed to OnSong along the way. Dropbox may show a different screen depending on what you have installed on your device.
Dropbox is a popular cloud-based storage service that offers 2 GB of free storage for signing up. You can pay a subscription if you need to store more information. 2 GB is more than enough space for chord charts and OnSong backups. Sign up at http://dropbox.com.
If you have the Dropbox app installed on your device, you will be redirected to that device to complete the authorization process. Check the account you are using and switch accounts if necessary. Once you are sure that the proper account is selected, tap on the Allow button to authorize OnSong to access your Dropbox and to return to the OnSong app.
If you do not have Dropbox installed, Dropbox displays a web-based authentication screen. Enter the email address you use to sign into Dropbox along with your password and tap the Sign In button. This will authenticate you with Dropbox and authorize OnSong to access your Dropbox.
Note: Both authorization methods are handled completely by Dropbox and no credentials are sent to OnSong at any time. OnSong requests access to your entire Dropbox to allow you to import and export files from any folder.