Push Notifications can be used in most every service that macOS Server 5.2 (for Sierra) can run. Any service that requiring Push Notifications will often provide the ability to setup APNS during the configuration of the service. But at this point, I usually just set up Push Notifications when I setup a new server. To enable Push Notifications for services, you’ll first need to have a valid AppleID. Once you have an AppleID, open the Server app and then click on the name of the server. Then click on the Settings screen and click on the checkbox for Notifications. At the Settings screen for your server, click on the check-box for Apple…