AdressBook Listener
<p>I am doing one application which should notify me changes (like update , delete, etc) in  contacts of addressbook ie <code>ABAddressBook</code> is used to get all the address contacts. I read that  <code>ABAddressBookRegisterExternalChangeCallback</code> will give notifications, but I am not sure how it will work. I wanted to store changes even though my application is closed. Let me know anybody has worked upon same or any inputs.</p>
