Had anyone implemented the PUSH NOTIFICATION SERVICE for the app to be stored for APPSTORE. If so please help me in finding solution for the following doubts I have: a) I found from the google search , that the 3rd party app server should ping the Apple server , then only the apple server will notify the app. If its so how to implement the 3rd party server to ping the apple server for sending notiications. b) Is the iphone sdk for 3.0 OS available for the development of appstore applications. Currently I am using the 2.0 OS SDK. Thank u.