I Need Advice

My cell phone, the little tank that it is, is dying after three years of faithful service. It's developed a distressing tendency to conk out on me when it claims it has full power, usually in the middle of phone calls.

So I need a new phone. But I know nothing about phones; cell phone technology has jumped since I got mine. I think that whole taking pictures thing is cool, and voicemail would be really, really cool, since this is my only phone line. My plan is with Cingular, and for a lot of reasons I won't go into right now, I can't switch, if that makes any difference as to what kind of phone I can get.

Tell me about cell phones, please.