objective c - Implement phone call lengh monitoring iOS -

I can call the user with my app. I want to get the length of the call in my app, when the call is finished

No, Can not get in the form. Once you start telprompt: // it will skip your application; Once the call is finished, the no representative is called later and you are out of your app. You can not access information related to any call in the non-jailbroke phone.