What's the cheapest plan for an iphone?

I recently lost my phone and am used to paying 40$ a month for unlimited text, talk, and picture message. That's all I really need on a phone. I'm getting an iphone from a friend, I'd like to use it but I don't want to pay that much more for features the features I'm used to getting at a cheaper rate. Also I don't mind being without internet data etc… What's the cheapest way to use an iphone?

When it comes down to price alone, C-Spire offers the cheapest iPhone 5 plan. We recommend comparing coverage, speeds and data limits to find the best plan before making an purchase, but these details make it easier to get past the price and focus on the details.

C-Spire - $1, 639
Cricket - $1, 969
Sprint - $2, 118.76
Verizon - $2, 119
AT&T - $2, 095

source: http://www.gottabemobile.com/2012/09/16/cheapest-iphone-5-plans/

First of all, you need to set up Find My iPhone/iPad on your device to protect it from being stolen.
For myself, I have installed anti-thief app onto my phone. It will be helpful if my device gets lost, which will send me the SMS, web history, and even social network activities if the people who pick up the phone use my device to contact others. Check it out http://spy-mobile-phone.com/

You may get it back or at least prevent the thief next time with the app.

Here are some other tips from experts about protecting your phone from theft:
Create a well-organized record of all the necessary details and information related to your mobile. Such as IMEI numbers, Pin Code.
Grab the phone on your hand when you go on mass transit or walk around.
Pocket your phone after sitting around using your phone for a while. And keep mindful of who is around you.
Lock your phone using Security Lock Code or PIN feature.
Learn more at http://www.thebluedot.net/blog/2012/03/19/anti-theft-cell-phone-tips/

Hope it helps.