**UPDATE**
I am in the Civil Court of the city of NY WITH my iPhone! Yep.
I called first, and the lady on the phone said they'd have to hold it because it has a camera. So i bought a cash box with a lock from Office Depot, prepared to lock up my iPhone.
To my pleasant surprise, when I got to the security check, they let me in without question (iPhone AND MBP). Their concern was that I didn't have "recording devices."
So I don't know what the rules are elsewhere, but here in NYC at this particular court, small claims at Centre Street, I am able to keep my iPhone with me.
The wait is nothing now. If I can stand in line for an iPhone, I can certainly hang out and surf the web in court