This article will guide you through configuring integration between SalesForce and DropBox, how to avoid user interaction to grant access to DropBox and also how to keep SalesForce notified about changes in DropBox.
There are some situations when you think it would be good to take files from DropBox, parse it in SalesForce and make some operations according to parsed data within SalesForce. Even more, it would be good if SalesForce could take required action right after the file has been changed or uploaded to DropBox.