I want an iPhone, but rarely use the phone?

I've been looking into getting a cell phone for a while, and I'd like it to be something I enjoy using. I own an iPod Touch 4g, which is fine, I can cal text, access everything and anything I need to. But that goes out of play when I don't have Wi-Fi. I'd like to get a phone, in case I ever needed to contact a family member for a ride, or any emergency purposes. I'd rather have myself put up the money for my own phone, and plan, but I don't want to pay an outrageous amount for a feature I rarely use. So are there any plans that would fit my situation best? Or a prepaid option? "Pay as you go"? I've read about some of the prepaid options for an iPhone 5, and the pros and cons of them, and the cons outweigh the pros from my perspective. I don't use the phone that often, but would like to have the option, and text from time to time. I've been looking at the iPhone 5, and 5s, if that helps any.

Any advice?

If you go to AT&T or someone like that you can pay about $20.00 a month for 3G and you have Wi-Fi everywhere you go.

I don't suggest you buy a iphone 5, as you don't use it often, it can be a kind of waste to buy it.

Complete waste of money. Buy a basic flip phone