You know when you're starting a new job and you have to wait a bit to feel out what you can "get away with" and what you can't. You learn that some things are ok as long as they don't interfere with your work. You also learn some things are just not ok. I am sort of waiting to see/hear about cell phone use - mostly for the text messaging. I don't want to take calls, but I do want to respond to texts.
For the first couple of shifts, I waited until I had my break. Then I got a little bolder and if there was a minute without clients waiting at the desk I would flip open the phone (from the vest pocket in which it had been hiding) and quickly read messages, but still wait until break to respond to them.
I think I have found some middle ground - texting during pee breaks. Yup, toilet texting (sorry Dad). I work shifts at many different times in the day. I just wanted to put that out there so that if you get a text from me, well, you never know what I could be doing. Grin.