functionality of Ti.Network.registerForPushNotifications

for Titanium 3.1.0 and iPhone 4.2- Please describe the functionality of Ti.Network.registerForPushNotifications when updated version of existing/already installed app is available or produced,

Also I am confuse with:- 1. When to show the update notification for app user in ipad 2. Which condition used to call Ti.Network.registerForPushNotifications 3. How the existing app find the updated version of same 4. Where to store the updated version of app for checking the condition with already installed app on ipad

                                         OR 

Is there any other way for alert/notification for updated version of existing app is available?

----Thanks in advance..