Upgraded my surface pro 3 to windows 10 when it came out. Before both the onenote desktop app and touch app would sync to my Office 365 work account. Now after upgrading to windows 10 only the desktop app can.
The touch app asks me to sign in but does not recognize my business account login. I have a Office 365 business premium account fyi. I can sync with onenote app on iphone, ipad, etc no problem.
I think this is a long standing annoyance that you can't use your office 365 business work account for many things including msdn.