I found this very well done short film,
that really shows how bad our cellphone craze sometimes has gone:
Has this ever happened to you or to your friends maybe?
Do you think it is rude to be on the phone in every situation and so on?
Where do you draw the line, if any?
I do not own currently a smartphone nor cellphone myself,
I just did not buy new one when my old one broke.
I have been in this situation and seeing this film made me realize that it is in fact quite rude to chat/text when you are having breakfast or lunch with someone.
Can you close your phone for hour or two?