ATT, if you get an iPhone, the data plan ( which is required ) is only $40 monthly. So you have unlimited texting, photo sharing, calling and free calling to other ATT members and landlines.
Location, Location, Location is the key to this suggestion. Some of us don't have good service from ATT! It is still 2G/EDGE where I live in Southern Illinois and about 25 miles from me there is a complete hole with NO service from them.