Mobile phones are becoming a pretty common feature in helicopters used in commercial ops in Oz and NZ. Provided they are secured in a cradle with the headset interface they are no problem at all, and no more of a distraction than having another radio. They are an excellent means of secure communication with company and certainly useful incase of a forced landing. While working in the Outback we also had an approvel to use a handheld Sat-phone instead of HF for remote ops.