I have a pong case which is supposed to dramatically reduce the radiation your phone emits.
It was awesome for my 4s, but the one on the 5s really sucks. My iphone totally cracked today and Mr. Bee's pong case is totally falling apart. (Side note: I contacted icracked and they come to your house within a couple hours to fix your phone for the same cost as the apple store!)
Thinking about getting this one from Anna Rifle Bond:
https://riflepaperco.com/shop/phone-cases/clear-rosa-everyday-iphone-5-5s-case/
Which one do you have? Do you love it?