Dropbox has quietly updated the terms for its free Basic tier. Free Dropbox users are now limited to three linked devices.
If that’s too confining, you’ll have to shell out for a $10 Plus or $20 Professional subscription. You can keep any links you’ve already established, but you won’t get to add any more until you go below that three-device maximum.
As kind of an aside, because I use iCloud instead of Dropbox, I wonder how much Dropbox would be affected if Apple added the ability to share entire iCloud folders, instead of just individual files.