Hi,
 I am using ContentObserver on contacts. But here my problem is atleast once i have to launch my application other wise i am unable to get notification chages. My code like this
ContactsContentObserver cco = new  ContactsContentObserver(handler);
    ContentResolver contentResolver = getContentResolver();
    contentResolver.registerContentObserver(RawContacts.CONTENT_URI,
    true, cco);
            }
private class ContactsContentObserver extends ContentObserver 
{
 public ContactsContentObserver(Handler h) 
 {
      super(h);
    }
    public void onChange(boolean selfChange) 
    {
       System.out.println("##########SOMEBODAY CHANGED ANYTHING AT THE CONTACTS");
       Toast.makeText(getApplication(),"####Updated####",Toast.LENGTH_LONG).show();
       }
....
Adv thanks. 
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