While on a call contacts information cannot be edited neither call log accessed
Seriously
I found out I could not edit a contact while I was on a call - this is is a much needed feature... who carries around pen and paper, only to enter it in there phone after conversation anyway.
i support and think thats a great idea
This is a real bummer for me. I have to write down the new information to add to contacts and after the call has ended only then I can put it in. More steps Apple. I know your goal is for your product to be simple . What I have to do in this case is not simple.