The Email Notification Service (ENS) adds Apple Push Notification support to Exchange. On iOS, this means the VMware Boxer and VMware AirWatch Inbox email apps can get notifications utilizing either Apple’s background app refresh or Apple Push Notification Service (APNs) technologies. Background app refresh is used by default, however iOS attempts to balance the needs of all apps and the system itself. This means that each app may provide notifications at irregular periods using this method. To provide notifications quickly and consistently, Apple also provides APNs. This allows a remote server to send notifications to the user for that application, however Exchange does not natively support this. ENS adds APNs support to your deployment to allow quick and consistent notifications about new items in your end users' email inboxes.