NO, Dropbox is one of many apps invented in collusion with Cell Phone metered data providers to help you to max out your data allotment so they can CHA-CHING you. (Files are automatically shared between Drop Box devices you see) but you have a good handle on how to work with it.
I have either not gotten any E-mails from them in a long time or.... My mail service is canning them in the spam can before I see them.. I use 2 E-mail providers, on one I check the spam can but I think I registered Dropbox with the other so every once in a while I change my account settings so I can delete a few thousand spam with 2 or 3 clicks. Then change back to "Classic" which won't let me do that.