What to say to a rude cell phone user
 
Say nothing. It's a setup. You are being goaded into pointing out their inconsiderateness so they can vent some of their pent-up anger. It's unlikely that you have the verbal communication skills to pull off a mutually satisfying conversation with them, one that will effect a positive change.

Theirs is a covert abusive communication rooted in a childhood incomplete. They are in fact addicted to abuse; they need their daily fix. If they can hook you into criticizing them then their reactionary upset gives them something to do other than experience the pain underneath their disregard for your serenity.

Keep in mind that all cell phone users have heard or read the articles—that others find it distracting, if not irritating, to have to listen to another's cell phone conversation. It's not as though they are "accidentally" being rude. They make this choice consciously, much like a barking dog owner does. They operate from a place of contempt and disregard for the space of others.

It could be that they are reminding you about space. 50% of the distance between you and another is your space, if another can hear your TV, etc. then you have intruded upon their space; in other words, who would say that you're intruding into their space?
 
Is there an alternative? Is there something you can do besides stuffing your upset thereby non-verbally empowering them to do it to another? The answer is yes.
 
After reading this article you'll now have another choice. You can hand them a copy of this tip. It's called service. It will serve them.

Like a driver who purposefully thwarts others by going less than the speed limit an inconsiderate cell phone user has yet to discover the correlation between their manners and the results they are producing in life and relationships. What they don't know is that they are looking for someone who won't buy into their act, someone who will support them in getting to the source of their anger.
 
Here are two possibilities that could come from your service: