I  hear people say that talking on you cell (wireless) phone in a public location, like a restaurant, is rude?  Ok.  Let take a look at this idea.

Question:

• Is talking to sum one that's with you (their) rude?   -  No?
• Yes , if talking its self rude.   -  OK?
• Or if done loudly.   -  OK?
• Is talking you children to same, ok too?
• Only if not done loudly, right? (This is far, the rudest!!!!).

So, it seems to me, that it should be OK, if it's ok to talk at all, at low volumes (quietly).
 

I think, the following should be, ones personal cellular (wl phone) rules:

• People with you, or in front you, have priority over the cell phone.
• Don't talk loud, may be talk even, more, quietly (louder doesn't make it work any better) (If others are having a difficult time hearing you, ask them to tell you what's the problem (like, static, braking up (it's not hard to do ;=), back round (noise) too loud, etc.
• If talking distracts you, then, may be this is a bad time for a call.
• If talking ties up you hands, then use sum type of hands free (head set) (Good idea anyway, it's safer).
• Lock ur phone (key pad (lock) to prevent accedental dialing, know how to un-lock it - read the manual).