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.

Mobile phones emit radiofrequency energy, a form of non-ionizing electromagnetic radiation, which can be absorbed by tissues close to the phone. The amount of radiofrequency energy a mobile phone user is exposed depend on many factors as the technology of the phone, the distance between the phone and the user, the extent and type of mobile phone use and the user’s distance from cell phone towers. (2)

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.
EMP Faraday Bags are designed to protect against damaging EMP current, static discharge, microwave transmission, RFID snooping and moisture damage. Protect your sensitive electronics (laptops, cellphones, iPads etc), precious memories (flash drives, floppy disks, tape recordings, etc) homeopathic remedies and medications, passports, credit cards and other devices from damage and spying. Could make all the difference if there is an EMP event or solar flare. Opening can be heat sealed with a hot iron for security reasons or long term storage. Manufacturer recommends that you “nest” items inside multiple layers of protection (double bagging) for best results.
The three most common brain tumor types — and the ones most cellphone and human health studies focused on — are gliomas (malignant tumors of the brain and spinal cord), meningiomas (mostly noncancerous tumors of the membranes surrounding the brain and spinal cord, though a small percentage are cancerous), and acoustic neuromas (noncancerous tumors on the main nerve that leads from the inner ear to the brain). Note that of these, gliomas are the main concern — they generally have more severe outcomes than meningiomas and acoustic neuromas.
Jump up ^ Christopher Newman, et al. v Motorola, Inc., et al. (United States District Court for the District of Maryland) ("Because no sufficiently reliable and relevant scientific evidence in support of either general or specific causation has been proffered by the plaintiffs, as explained below, the defendants’ motion will be granted and the plaintiffs’ motion will be denied."). Text
A decline in male sperm quality has been observed over several decades.[11][12][13] Studies on the impact of mobile radiation on male fertility are conflicting, and the effects of the radiofrequency electromagnetic radiation (RF-EMR) emitted by these devices on the reproductive systems are currently under active debate.[14][15][16][17] A 2012 review concluded that "together, the results of these studies have shown that RF-EMR decreases sperm count and motility and increases oxidative stress".[18][19] A 2017 study of 153 men that attended an academic fertility clinic in Boston, Massachusetts found that self-reported mobile phone use was not related to semen quality, and that carrying a mobile phone in the pants pocket was not related to semen quality.[20]

to find the minimum distance the federal government recommends that your cell phone must be away from your body. Keeping it closer than the designated distance can result in a violation of the FCC Exposure Limit. Exceeding FCC levels is proven to result in burns, sterility and brain damage. Learn more about fine print instructions and see all the FCC warnings here.
What the study showed: Most published analyses from this study have shown no statistically significant increases in brain or central nervous system cancers related to higher amounts of cell phone use. One analysis showed a statistically significant, although modest, increase in the risk of glioma among the small proportion of study participants who spent the most total time on cell phone calls. However, the researchers considered this finding inconclusive because they felt that the amount of use reported by some respondents was unlikely and because the participants who reported lower levels of use appeared to have a slightly reduced risk of brain cancer compared with people who did not use cell phones regularly (4–6).