Studies have shown that 95% cases of cancer are caused by radiation from cell phones and other electronic magnetic devices. It is advised not to use your cell phone when the battery is bellow 30% and when on long call ear piece should be used. Even at that the phone still get over heated and this heat radiation causes one of the major health issues to be body such as cancer,depression etc.
It is better to use Anti-radiation stickers on your mobile phones and other gadgets since it helps prevent phones from overheating and also reduces 98% of radiation from your mobile phones.