New research suggests that hunching over your phone could produce horn-like growths at the back of the skull, just above the neck. It's been known for many years that cellphone use can lead to so-called tech neck, which is caused by contorting the head to look at your handheld device. It can also cause poor posture, neck and back pain, and headaches. To solve the issue, there are simple exercises you can do, and make sure to always keep your phone at eye level and don't look down.