“Yes, “hosted” means an organization does not own and run its own email servers at its business location, but instead relies on email servers that reside at a site belonging to another organization. Thus, a hoster could be a company like RackSpace or 1 to 1, which offer to “host” Exchange servers that they run, for the benefit of a third party organization; or could be Microsoft via Exchange Online and Office 365.
With respect to Exchange specifically, we usually refer to “hosted email” as the first option above, vs. EXO or Office 365. “Hosted email” in the first example is exactly the same admin and end user experience as if the organization owned and ran their own email servers, vs. the Groups/Delve/Graph etc integrations in Office 365.”
“"Hi Brian, that should work provided you have the Skype for Business client installed on the mobile phone, and you have a data connection. You can download the app from the respective app store. If you've done that and calls still do not arrive, probably best to contact O365 business support. Information on that is at