GP refers to the controversy around how you should hold an iphone so it doesn't lose reception. First few versions had a receiving system which could be easily

GP refers to the controversy around how you should hold an iphone so it doesn't lose reception. First few versions had a receiving system which could be easily interfered with by not holding it right (shorting notches on the outer rim) if you were used to hold a phone at the top, i.e. palm at your ear (vs cheek). Jobs suggested to not do that.