What’s the best replacement for Ubuntone?
In times of the NSA spying the whole net I would recommend to setup or rent your own server and put owncloud or pydio on it.
I’ve gone for Insync Plus and Google Drive. Unlike some others it works with the directory structure without my having to create links personally. Also it is cheap. SpiderOak looked like a possible, but I went for cheap, as I don’t need all those bells and whistles. So far so good.