Cell Phones, Smart Phones and Acceptable Use

In an effort to complete as much as possible, I would like to initiate an informal discussion of technology use concerning cell phones outside of class. In the technological age of Hawken with the one to one program,  the ever-increasing utility of cell phones, and the ambiguity between tablets and cellphones I would propose that students should be allowed to use their cellphones outside of class in any way as long as they are not talking on the phone or disturbing anyone. Essentially, the only major difference between smart phones and tablets is the call and text functionality that runs over a cellular network. If calling people is prohibited, that just leaves the text functionality with which to be dealt. There really is no difference between abundant instant messaging programs (such as facebook messenger, AIM, google+ etc etc) and the text functionality found on phones. Allowing someone to use a messaging program but prohibiting text functionality in phones just seems pointless.
Now, the main point of discussion and potential objection would be somewhat analogous to the headphone argument, involving politeness and safety and social interaction. I would argue that the focus of this discussion should be the mobility with cellphones, and not the use in areas such as the AC lobby and pronto room. Again, there really is no difference between cell phones and tablets so if a student is allowed to use a tablet in one area, they should be allowed to use a cellphone there. If someone is sitting in the AC lobby being antisocial on their smartphone, they could just as easily, if not even more easily be antisocial on their tablet. Back to mobility, I do not have an opinion either way, but I am leaning towards the idea that kids should not be able to walk in the hallways whilst on their phones because it takes the visual attention away from the individual, and we don't want students to walk into people and walls etc etc.

So what does everyone else think?