Rude cellphone users are anywhere that there's a cell phone signal. Most people who are being impolite don't even realize what they're doing. Could that be you?
1. The First Principle: It is not other people's responsibility to cope with your mobile phone use; it is your responsibility to use your mobile phone inoffensively. Please note that "inoffensively" is not defined by what you expect others to tolerate, but by what others do in fact find offensive. Ignore this principle, and you are sure to be rude.