The point in a cell phone conversation were one person begins loudly verbalizing their disapproval, discomfort, or other negative emotion. This person usually attracts a lot of attention, and surrounding public may be inclined to ask the person to quite down.
Oh man! Yesterday I was on a date with Lisa, when Stephanie called and told me she had STDs. I totally went yellular on her and rode her ass about how that was so not okay with me.
Then the waiter came and told me to take it outside, so I decked his ass and left.