EWG met with representatives of Pong Research and fully agrees with its business premise that cell phone cases should decrease, not increase, radiation exposure. Pong hopes to carve out a niche by selling cases that lower the phones’ radiation exposure. We anticipate that as awareness of the potential risks of cell phone radiation grows, Pong and other companies will respond by marketing cell phones and cases that offer users good communication with less radiation.
Our homemade demonstration of all the cases uses a working phone. Not the shielding material by itself, but the actual "shielding" SafeSleeve, Pong, Reach,  Vest, ShieldMe, and Defender Shield cases. First we get RF power density measurements from a phone that's on a call and then, in the same location, within minutes of the first reading, we place the same phone as it's engaged in a call into each case and we take additional reading with the meter.
The government, however, does not require phone manufacturers to consider the effect of cases when they conduct compliance tests to meet the FCC’s allowable radiation exposure limits. The significance of this omission was underscored by tests commissioned by case-maker Pong Research and submitted to the FCC in May 2012. Those tests showed that three models of cases made by competing companies and used with an iPhone4 increased the phones’ Specific Absorption Rate, or SAR – the amount of radiation absorbed by the user’s body – by 20-to-70 percent (Table 1).
Pong Research also makes cases for the iPad and its technology is arguably better suited for that. Why? Because serving as a stand to prop up your iPad or tablet, it means you don’t really need to hold it. That’s an ideal setup because higher amounts of radiation are going out the back, versus the front of the screen which you are touching with your fingers and palms.
Bonus application! In addition to shielding magnetic fields, PaperSHIELD is also quite good at shielding radiowaves (cellphone, wifi, etc). And because of the adhesive backing, it can be adhered to almost any surface you need such as the inside or back of your cellphone case. (Use a near field meter to test RF shielding performance.) Note that it is not transparent, so it can't be used on the touch screen side. Cover the cut edges with sturdy tape as they can be sharp. 36 inches wide. Made in USA.
In addition to the increased brain cancer risk, in male rats there was also “clear evidence” of a link between the radiation and malignant heart tumors and “some evidence” of a link to adrenal-gland tumors, according to the release. In mice and in female rats, however, the link between radiation and tumors was “equivocal,” or uncertain. The hierarchy, from most to least certain, of characterizations used by the NTP is: “clear evidence”; “some evidence”; “equivocal evidence”; and “no evidence.”Today’s cellphones use higher-frequency radiation that is less able to penetrate animal tissues than the radiation used in the study, the Times reports. Further, since cellphones became popular, epidemiologists have not observed an overall increase in the frequency of brain cancers known as gliomas in humans. 
The only consistently recognized biological effect of radiofrequency radiation in humans is heating. The ability of microwave ovens to heat food is one example of this effect of radiofrequency radiation. Radiofrequency exposure from cell phone use does cause heating to the area of the body where a cell phone or other device is held (e.g., the ear and head). However, it is not sufficient to measurably increase body temperature. There are no other clearly established effects on the human body from radiofrequency radiation.