I was kidding when I was speaking of satelites phones.
We all know cell signal will never be in all places.
But if I were stuck in the middle of nowhere, I would rather have on hand a satelite phone (expensive to use per minute, and have a signal, than a dead cell phone).
I was on c/net,and this website showed the replies of people who had different carriers in several cities.
I wanted to thank the person who suggested to me.
Thank you for your time taurus.