There were no biological hypotheses tested in the study. It was therefore only a numbers game. Ignored were mechanisms of disease found in other studies of cell phone radiation effects, including genetic damage, blood-brain barrier leakage, and disrupted intercellular communication. The study did not discuss any research supporting the notion that cell phones could cause problems in users.
So, what types of RF are these cases intended to block? If they block the frequency being used by the phone than if the blocking is complete the phone won’t work. If it’s partial than, as noted by the FCC and related in the article, the phone may attempt to compensate for the weakened signal by increasing it’s signal strength, thereby emitting higher levels of radiation itself, and reducing battery life in the process.
Third, most of the studies published so far have focused on adults, rather than children. (One case-control study looking at children and teens did not find a significant link to brain tumors, but the small size of the study limited its power to detect modest risks.) Cell phone use is now widespread even among younger children. It is possible that if there are health effects, they might be more pronounced in children because their bodies might be more sensitive to RF energy. Another concern is that children’s lifetime exposure to the energy from cell phones will be greater than adults’, who started using them at a later age.
We couldn't find one legit EMF expert online or anywhere else that would recommend a radiation blocking case or anti-radiation case. Not the Environmental Health Trust or Magda Havas, or Joel Moskowitz, in fact his site, safeEMR cautions against scams and claims for radiation protection.  So if a so-called "EMF expert" is recommending any kind of anti-radiation case, they probably aren't that much of an expert. 
The company's "Researches" page, for example, states that "Aires Technologies are more than 12 years (sic). For this period there have been conducted a number of studies on mechanisms of coherent transformers that effect on physical, chemical, technological and biological processes (sic). The studies were carried out in close collaboration with leading research and academic institutions."
That’s why the International EMF Scientist Appeal and a number of health and safety organizations, including the American Academy of Pediatrics and the Environmental Health Trust, have called on the government to reassess the safe levels of exposure to cellphones and other wireless technology and then develop new consumer safety guidelines based on those assessments, Moskowitz said.
It’s also possible that longer-term studies and cancer incidence tracking will find larger cancer effects in another five or 10 years — or that how we use cellphones is evolving such that the devices may cause cancer in ways these studies didn’t account for. (These days, many people text instead of talking, and hold their cellphones in their pockets but not on their heads and necks.) That’s why some people look to animal studies to supplement our understanding of the potential biological effects of cellphones.
Morbidity and mortality among study participants who have brain cancer. Gliomas are particularly difficult to study, for example, because of their high death rate and the short survival of people who develop these tumors. Patients who survive initial treatment are often impaired, which may affect their responses to questions. Furthermore, for people who have died, next-of-kin are often less familiar with the cell phone use patterns of their deceased family member and may not accurately describe their patterns of use to an interviewer.
Cell phone radiation refers to radiation in the form of electromagnetic waves that is emitted from mobile phones. This type of radiation takes the form of radio waves that are near the microwave range. The amount of radiation that a given cell phone will emit depends on the exact frequency of the radiation, as well as whether the device is using an analog signal or a digital one. There has been speculation that large amounts of cell phone radiation could be hazardous to the user's health, but there are no conclusive scientific findings on the subject.
The papers found that, in male rats, there was “clear evidence” that exposure to cell phone radiation increased risk for a rare type of malignant tumor called schwannoma in the connective tissues that surround nerves in the heart (they found “equivocal” evidence for the same thing in female rats). They also found “some evidence” that the radiation caused malignant glioma—a type of brain cancer affecting glial cells—in the male rats.
Released in 1993 as a joint creation of IBM and BellSouth, this was the first smartphone. A fax machine, a PDA, a pager and a mobile phone, the IBM Simon featured no physical keys, but used a touchscreen and optional stylus. Amazingly, it included applications such as games, email, a notepad, calculator, world clock, address book and a calendar. It only sold in the United States, for $899.
"For example," Johnson said, "what does a fractal like pattern have to do with a hologram? The answer is, of course, nothing that is apparent. Then there is a truly convoluted assertion that cell phones can be instrumental in ‘psychoemotional' effects on humans because of their lower-frequency outputs. This too, is gibberish. In short, this is technobabble that will potentially snow someone who has no science background."
In order to protect the population living around base stations and users of mobile handsets, governments and regulatory bodies adopt safety standards, which translate to limits on exposure levels below a certain value. There are many proposed national and international standards, but that of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) is the most respected one, and has been adopted so far by more than 80 countries. For radio stations, ICNIRP proposes two safety levels: one for occupational exposure, another one for the general population. Currently there are efforts underway to harmonise the different standards in existence.[26]
In subsequent analyses of Interphone data, investigators addressed issues of risk according to specific location of the tumor and estimated exposures. One analysis of data from seven of the countries in the Interphone study found no relationship between brain tumor location and regions of the brain that were exposed to the highest level of radiofrequency radiation from cell phones (9). However, another study, using data from five of the countries, reported suggestions of an increased risk of glioma and, to a lesser extent, of meningioma developing in areas of the brain experiencing the highest exposure (10).