My company suddenly jumped to Office 365 recently. We now have to use the "Mobile" versions of all Office apps (they don't even appear in the Windows Store search for me). It feels like a preschool version of an actual Office Suite.

We've been testing Teams for a week and nobody has used it ever since. It doesn't delivers a message and then it disappear; the calls often work only one-way. To use it on Linux, you have to fake your user-agent. It's laughably bad.