What is Push Notification exactly?

Ahh boo.

 

apps that have it enabled or built in it essentially connect to a server 24/7 and where is an update it sends a notification to your phone whether it be the form of a badge, text, or audible alert

 

No.

Remember the little cloud demonstration Apple gave for the release of MobileMe? It's basically the same thing. Difference is your account on the application utilizing the Push service remains active even after you close it on your phone. It is still able to receive messages. When there is an update in the status of that application, the push server sends a signal to your phone which translates into a sound or badge.

That's about as simple as it's going to get. You want technical terms somebody else is gonna have to take the floor.

 

Basically like specialized SMS messages.

 

i like your example better lol!

 

This is about as simple as it gets. Basically what happens now for say ... Email is you set your iPhone to "Fetch" the information every 15 minutes or 30 minutes or so. So while you're on Fetch your iPhone has to go check for messages every 15 minutes or so, even if there is nothing new ... That wastes battery life. PUSH is when the service, like GMail sends a little message "Basically like specialized SMS messages." which sends the new message to your iPhone.

 

The idea is that a single watcher process replaces all background processes that usually are constantly checking for something new on the net. Instant Messaging, weather alerts, stuff like that.

1) Instead of the apps running on your phone, they run on a server somewhere.

2) When they need to alert you, they send a short notification message directly to Apple.

3) Apple then passes it down to your phone's single background notification process, which is waiting for them. You see or hear the short alert, or hopefully notice a badge number change.

4) You open the app, and it goes out directly to its server and asks for details.

 

Ok - this is slightly tangential, but I know you'd be the one to know kdarling - Would it be crazy to say that Google Wave could be Google's PNS?

Not for apps at the moment, but the thought of having a single background notification process?