I basically only use Dropbox because it is supported on Linux. Also its syncing technology is sooo much better than Google Drive you would think Drive was built by interns. However, they are taking their sweet time with newer features like Smart Sync. It's disappointing because I'm paying for these features and yet they're not supported on one of the platforms my whole company uses. All in all I really hope Dropbox doesn't keep chipping away at Linux - I fought hard internally to use it and I don't want to be proven wrong.

There's a decent open source sync daemon for OneDrive on Linux - I'm the packager who looks after it on Fedora. With the odd exception when APIs change it just works.

What daemon is that?

https://github.com/abraunegg/onedrive (currently I package the original project by @skillion, but this fork is better maintained...)