My T has her office phone on silent during sessions and I don't see her cell phone anywhere in sight. It seems like common courtesy for that profession. One time her fax machine kept printing stuff and she excused herself to turn around and removed the paper from the feeder so it would stop printing and making noise. I think I would have issues if my T kept checking her cell phone like you describe. It seems rude to me that she even has it out, especially after you were honest about how it makes you feel when she keeps checking it or pressing buttons on it during your time.