If you are curious on how the Push-Notification works on the yet to come iPhone 3.0, here are the details.
Apple has been testing their push notification system with a preview edition of the AP News app; this app is made available to selected developers only on the iTunes Store. Of course, this new app requires iPhone OS 3.0 and breaking news is supposed to be notified even when the app is not running. So here is how it looks like:
1) When you launch the app for the first time, you're asked if you want to enable push notification. Let's answer OK.
2) Well, you are good to go now, but lets see what can be configured. Go to Settings (of your iPhone) and you'll see a new item called "Notifications".
3) Then you will see a list of apps that uses the push notification service.
4) You can then configure three settings for each app; you can be notified by: 1. Sounds, note that the app developer decides what the tune will be, not you, 2. Alerts which is a pop-up, 3. Badges, the little red circle with a number of unread messages like the Mail app.
So now, how does this work in live? Badges, there is no need to explain. The Sounds, umm, it would be nice if the user can choose a tone like the ringtones; it probably will depend on the app, but the AP News buzz sound is not good for ones heart. Also, it might be nice to have a time schedule in which you can turn it off at night. Alerts is like when you get a text message; it looks like below:
BTW, if you are curious, it does work with both carrier network or Wi-Fi. In the above picture, the phone is in Airplane mode with Wi-Fi on, although the Wi-Fi icon is not on. (May be it works without any Internet connectivity. You know, Apple is very innovative so…)
Now, my opinion on this: I think this really does not replace background processing. For example, with the AP News app, you launch the app after receiving a notification which takes at least few seconds. Then, the app really doesn't show you the related article; or at least it wasn't obvious to me. Think about using this with an IM app, constantly switching apps going back and forth with another app, each time logging in and out of your IM session. The notification is not delivering messages to the app, it's just a notification; after the app is actually launched, it still has to load information via the Internet and the app has to be well developed so that it actually is in sync with the notification message. All this is going to take so much time that users will defiantly start to complain.
Push Notification is probably for applications such as emails or news updates. If you are playing games, doing some research on the web and wanting to IM chat with someone going back and forth, this is not yet the solution.