[kfk]

The worst thing for me is not being able to sync only 1 folder instead of the whole thing. When you are syncing a mobile phone, you don't want to be downloading GBs of stuff, maybe only 1 folder with your resized pictures...

[acdha]

The mobile app has never downloaded everything.

The desktop app allows you to select a subset of folders to sync: https://www.dropbox.com/en/help/175