I really want to caution you to be careful of any "expert" or EMF blogger recommending anti-radiation filtering cases, stickers that attach to the phone or necklaces to "ward off" EMF. I get it, when I first realized 25 years ago that I was sensitive to electromagnetic energy and then later, when I understood that without a doubt, man made electromagnetic radiation has a biological effect on my body, I wanted an easy fix. I tried the shielding materials and cases and I just did not feel any better. Then I bought meters to see if the energy changed and I actually noticed what the California Department of Health now says and it's what the FTC and FCC post warnings about: "Some shielding materials can make exposures worse". So please, be careful and read on for what you can do to avoid electromagnetic radiation exposure.
The Specific Absorption Rate that the FCC, with input from many other government institutions, decided on, is defined using an average of a 30-minute phone call with the cell phone held directly to the ear. Since modern cell phones are used in all sorts of manners, ie speakerphone, scrolling through social media, browsing the web, etc, a base had to be set.
A cellular phone is basically a radio that sends signals on waves to a base station. The carrier signal generates two types of radiation fields: a near-field plume and a far-field plume. Living organisms, too, generate electromagnetic fields at the cellular, tissue, organ, and organism level; this is called the biofield. Both the near-field and far-field plumes from cell phones and in the environment can wreak havoc with the human biofield, and when the biofield is compromised in any way, says Dr. Carlo, so is metabolism and physiology.
I liked the way Blocsock implemented this protection and the quality of the product construction, combined with the validated test results, so I recently ordered ones for the rest of my family. I think Blocsock is the BMW-class of what I could find for products that protect against cell phone radiation. My wife has a larger Droid phone and it fits in the case (just barely though)! I hope the makers consider making a larger model for all the new, larger smartphones that recently came out with the larger screen sizes. Again, check to make sure your phone fits, which a friendly message to the company will answer if you are not sure.
The device comes in a variety of forms ranging from the $39 Aries Shield ("a silicon based micro processor that ... decomposes oscillations of electromagnetic fields") to the $249 Aires Defender Utility (which "has two next generation 9 core silicon based micro processor (sic) that provide universal protection from electromagnetic smog of the broadband frequencies").
Finally, the measurement of cell phone use in most studies has been crude. Most have been case-control studies, which have relied on people’s memories about their past cell phone use. In these types of studies, it can be hard to interpret any possible link between cancer and an exposure. People with cancer are often looking for a possible reason for it, so they may sometimes (even subconsciously) recall their phone usage differently than people without cancer.