We recently signed agreement on o365. We are planning to kick of SharePoint on-line, yammer implementation project including migration from SharePoint on-prem.
But exchange on-line project will go live after SharePoint on-line implementation. In this regard we would like to know dependencies of SharePoint on-line, yammer on exchange on-line.
For example we came to know the following cannot be done configured without exchange on-line.
1) Adding custom tiles in app launcher
2) Site mailboxes