Push notifications are alerts, badges, or sounds which are pushed to a mobile device from a remote server. Apple delivers push notifications via the Apple Push Notification Service (APNS). Android devices receive push notifications via the Google Cloud Messaging (GCM) service. In the past, Android devices used the Cloud to Device Messaging (C2DM) framework. Windows Phone apps receive push notifications either via MPNS or the newer WNS.
Push notifications are alerts, badges, sounds and/or data which are pushed to a mobile device from a remote server.
In ios, push notifications are delivered via Apple's Apple Push Notification Service (apns), triggered by a message from developers' servers to Apple's APN servers, which in turn push the message to iOS devices. Apple first released push notifications in iOS 3.0. Push notifications should not be confused with local notifications, which are a way for an app to post a notification to a device locally, with no interaction with push notification servers. New in ios7, you can add flags to push notifications to make them silent or to trigger a background fetch.
In android, push notifications are delivered via Firebase Cloud Messaging (fcm). (Previously called Google Cloud Messaging (gcm)). This replaces Google's Android Cloud to Device Messaging Framework (c2dm).
Push Notifications for Windows Store apps are delivered via the Windows Push Notification Service (wns), which enables third-party developers to send toast, tile, badge, and raw updates from their own cloud service.
Push Notifications for Amazon devices running kindle-fire (Kindle tablets, Fire TV and Fire TV Stick) are delivered via the Amazon Device Messaging (adm) service.
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