A common pharse said to one of your friends when you are leaving for a second to use the bathroom go to the vending machine etc... You entrust your valuables like your northface bag, your coat, ipod or anything that could be stolen in your absence.
When you have a shitty old pre-paid phone because you or your parents are too cheap to buy a blackberry or android. Phone shame also happens when you have a flip phone or something from metropcs and you are just too embarrassed to take it out in front your friends because it is just so old, bulky, or ugly.
Ross:Hey whats your phone number
(Brian takes out crappy flip phone)
Ross: Tuff cell kid whats the a Razor flip phone, that shit was cool when I was in 4th grade.
Brian: Yea, I have a bad case of phoneshame.
Ross: HAHA! IT STILL HAS A CINGULAR LOGO ON IT