The Apple Push Notification Service (APNS) delivery channel allows Connect to deliver APNS notifications to iOS and MacOS applications running on iPhones, iPads, and MacOS computers. In Apple terminology, a provider originates push notifications and transmits them to the Apple push notification gateways. The destination devices (iPhones, iPads, etc.) maintain connection to the same push notification gateways to receive the push notification messages on these connections.
The APNS Delivery Channel allows Connect to serve as an APNS provider. In order to connect to the APNS gateways, Apple requires the provider to use TLS peer-to-peer authentication using a server certificate provided by Apple. This Apple-provided certificate is required to configure an APNS delivery channel.
When an iOS or MacOS application registers with the APNS gateways, it receives a binary device token that identifies the application running on a unique device. This device token must be stored in the APNS channel customer attribute for each customer before Connect can send notifications to that customer.
The APNS delivery channel may be used to deliver notifications to multiple iOS or MacOS applications. Each application must be configured as a separate delivery channel, with a unique name, Apple-provided server certificate, and customer attribute to store the device token.