Our faculty is about evenly split re cell phones in class. I have chosen to advise my students to leave them on vibrate, and to step out to take a call if they must. They are adults with children, pets, houses, etc. In addition, I have come to see cell phones as a safety device. If an angry or distressed student were to enter my room, students whose cells are on can call for support, or text others to take necessary action. What do others think?