What is everyone using for shared staff calendars?
We currently use Public Folders and have been for a long time and it does what we need but there is not a native app for iOS and the third party Public Folders app is flaky.
We looked at the new O365 Groups but currently you cannot lock down the groups calendar to where only certain people can add items. Microsoft did add some power shell options to keep members from changing or deleting items but any group member can still add items and this is a deal breaker.
I have one client left on Google and the rest are on O365. Google is far more straightforward on the calendars and permissions for read/write/owner permissions. With O365 there are a couple of ways to do it but it isn’t as straightforward because you either have to drill down into the exchange admin interface and create a shared mailbox (and then assign admins and whatnot) or you need to setup a group and manipulate the permissions of that group. My churches all have highly permissive attitudes toward staff and regular office volunteers adding or editing events on the calendars so O365 hasn’t been much of an issue.