I am new at iPhone development. I want to access iOS6 call_history. My code work for iOS5 but not work for iOS6. please help me to solve this problem. Many Thanks.
You cannot access the call log using the SDK and approved APIs. There are some workarounds, as you probably already know. The only option I know about is accessing call_history.db.
Take a look at this tutorial. Unfortunately for you, security has been made more severe, and you only can access that file in iOS < 5.0 (and probably all jailbreacked versions).