According to a Mar. 2008 meta-analysis of cell phone studies there is a "consistent pattern" connecting cell phone use and an increased risk of developing glioma, a type of brain tumor.  A Mar. 31, 2009 study found that long term cell phone use (10 years +) "approximately doubles the risk" of being diagnosed with glioma on the same side of the head where the cell phone is held.  In Apr. 2013 another study of Swedish cell phone users also found an association between cell phone use and the development of glioma and acoustic neuroma - a benign tumor formation on the nerve near the ear.  That study’s conclusions were confirmed by a different study in Apr. 2014.  Other studies published from 2005-2013 have similarly concluded that there is an association between cell phone use and increased risk of developing brain and head tumors.    
It is concluded that radiofrequency radiations are genotoxic as they induced chromosomal aberrations in chickpea mitotic cells and the presence of ghost cells is clear indication of their carcinogenic potential. To avoid reported DNA damages in this work cell phones should always be used either for short duration or with hands-free for long duration and they should not be kept in pockets or near body. Laptops should not be used unnecessarily for enjoyment purpose. It must be placed on desk top rather lap to minimize their exposure to human body. Further assay of carcinogenity are recommended on mouse and human cell lines.
“See a name you don’t recognize? Get the lowdown on the mystery texter by conducting an online background check. Pull their criminal records to discover if they’ve potentially been convicted of anything serious, such as a sexual offense or other violent crimes. Being armed with this information is the first step to squashing your teen’s inappropriate relationship.” – Logan Strain, Who Has Your Kid Been Texting? Guarantee Cell Phone Safety with These Tips, Instant Checkmate; Twitter: @instntcheckmate
The purpose of this study was to reveal whether long term exposure (over a year) of 2.4GHz frequency RF radiation will cause DNA damage of different tissues such as brain, kidney, liver, and skin tissue and testicular tissues of rats. Based on the DNA damage results determined by the single cell gel electrophoresis (Comet) method, it was found that the % tail DNA values of the brain, kidney, liver, and skin tissues of the rats in the experimental group increased more than those in the control group. The increase of the DNA damage in all tissues was not significant (p>0.05), however the increase of the DNA damage in rat testes tissue was significant (p<0.01). In conclusion, long-term exposure to 2.4GHz RF radiation (Wi-Fi) does not cause DNA damage of the organs investigated in this study except testes indicating that testes are more sensitive organ to RF radiation.
In response, we would state that all wireless frequencies currently used by the public are categorized as radiofrequency radiation. People have not been using Wi-Fi for as long as they have been using cell phones, so the research that has looked at long term use of cell phones is very important in considering the long term health risks from wireless and Wi-Fi specifically.
The FCC sets the maximum amount of thermal radiation (heat) that cell phones are permitted to emit.  This limit is measured as the amount of radiation absorbed by a user and is known as the specific absorption rate (SAR). In 1996 the SAR for cell phone radiation was set at a maximum of 1.6 watts of energy absorbed per kilogram of body weight. Manufactures of cell phones must test their products to ensure that they meet this standard. Random tests of phones on the market by FCC scientists further ensure that radiation levels meet FCC guidelines. 
This study was aimed at investigating the alteration of antibiotic resistance of Klebsiella pneumonia, after exposure to Wi-Fi 2.4 GHz electromagnetic radiofrequency radiation from a Wi-Fi router for 3, 4.5 or 8 hours. The findings of this study show a statistically significant rise in the sensitivity of Klebsiella pneumoniae to different antibiotics after 4.5 hours of exposure to 2.4 GHz Wi-Fi radiation, followed by a fall after 8 hours of exposure. These observations can be interpreted by the concept of non-linearity in the responses of Klebsiella pneumoniae to different antibiotics after exposure to electromagnetic radiofrequency radiation.
43. Search for the unknown callers. Discovering unknown or anonymous numbers on your child’s phone can be alarming, but a bit of detective work can lead you to answers. “Now that you know who your kid chats with, you can see if there are any messages that make you suspicious. If you spot a phone number you don’t recognize, do a reverse phone lookup to discover exactly who they are talking to. By searching any domestic number, you may discover the texter’s name, carrier, and address.
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.