It’s not necessary to share an entire Dropbox folder just to give someone access to a single file. You can send a link to a file in Dropbox to just about anyone. You can do it from your Dropbox web account or, if you have Dropbox installed on your computer (you’ll see Dropbox in your Finder/File Manager), you can share a link from your desktop. Here’s how.
Control/Click the file in your file manager, then choose Share Dropbox Link.
Dropbox will automatically save a copy of the link in your clipboard and you can then paste it into an email or text message.
By sharing from your web profile, you have more control of the “terms” of your shared link. Just click the Share button to the right of the file, choose your settings, address it and send a note if you wish. You can assign a password and set an expiration date. After that date, the link will no longer function.
Using the web interface, you can choose visibility and duration then forward via email or text.
Got a huge GEDCOM you want to send a cousin? This could be a great way to do it.