Exchange Online gives companies a majority of the same benefits that on-premises Exchange deployments provide. Users connect to Exchange Online via the Microsoft Outlook desktop client, Outlook on the web with a web browser, or with mobile devices using the Outlook mobile app to access email and collaboration functionality, including shared calendars, global address lists and conference rooms.
Administrators use the Exchange admin center to tweak features in Exchange Online, such as the ability to put disclaimers in an email.The Exchange admin center is a centralized management console used to adjust Exchange Online features, including permissions, compliance management, protection and mobile to configure mobile device access.