Some of our Therapists use iPod Touch to chart. As for the nurses, I believe we can use them in break room/lounges but not on the unit. However, there are times when I am at the nurses station (and ONLY the nurses station) and need to look something up and use my Android to look up medications, procedures, test results etc etc via Medscape, Davis, Epocrates and no one has ever said anything to me about it.
For me, using technology in my nursing career is incredibly helpful and I wish more people went in that direction. I used an iPod Touch throughout nursing school because it was easier than carrying around 75lbs of books to the unit during clinical.
TL;DR = some people use them to chart and for references but in general it should only be used in break rooms and lounges in our facility.