Beginning iOS 5 Application Development

19

Programming Remote Notifications Using Apple Push Notification Services

WHAT YOU WILL LEARN IN THIS CHAPTER

• How to use the Apple Push Notification service
• Generating a certificate request
• Generating a development certificate
• How to create an App ID
• How to configure an App ID for push notification
• Creating a provisioning profile
• How to provision a device
• How to deploy an iOS application onto a device
• Using a push notification provider application

One of the key limitations of iOS is its constraint on running applications in the background, which means that applications requiring a constant state of connectivity (such as social networking applications) cannot receive timely updates when the user switches to another application.

To overcome this limitation, Apple uses the Apple Push Notification service (APNs). The APNs enables your device to remain connected to Apple's push notification server (PNS). When you want to send a push notification to an application installed on the users' devices, you (the provider) can contact the APNs so that it can deliver a push message to the particular application installed on the intended device.

In this chapter, you will learn how to use the APNs to push messages to users who have installed your application.