I have Verizon because it has coverage even AT&T doesn't have. I love my I-Phone 4. My husband has a Samsung because it has the bigger screen, but I don't like his because I have trouble seeing the screen outside. Both my daughters have the I-Phone 5.
In San Diego if you go to Best Buy they can help you activate your phone with Verizon. If you buy your phone at Verizon for a discount that is when you have the 2 year contract nonsense. If you buy the phone and activate it thru Verizon you don't have to do the long contract. My daughter went to Best Buy to get a "hot spot" and they told her that since we were with Verizon, that we should go thru them for a better deal. It was a better deal, my bill was reduced by $30.00.