Bending your neck in this manner can cause a condition named occipital neuralgia.
Occipital neuralgia is a condition that occurs when the base of the nerves become compressed or damaged. This can cause really terrible headaches which occurs between the back of the neck and the beginning of your hairline at the back of your head.
This condition is a common problem that comes with smartphone addiction (when you can’t help but go through your smartphone too many times). Tilting your head forward at a 60 degree angle can put a lot of pressure on the top of your spine and surrounding muscles and cause indefinite pain.
So when next you are about to ‘look down’ on your phone, remember occipital neuralgia.