I was taking a look at iphone apps that will do medical math for you in the field. Being not so great at math, and in medic school, I'm a little concerned about this aspect of the job. So I'm looking for opinions - do you use these apps or know anyone who does? How accurate are they? If you have used them, have you had patients react negatively to the fact that you're looking at your phone when you're supposed to be taking care of them?