At what age should a child get a phone?

[KIRZZ]

My 12 years old brother wants a cellphone. My parents are discussing about the consideration to have his first phone. In my opinion, he still needs to prove that he is responsible for using a cellphone. As an adult, I am aware of the danger of using the internet. Also, he tends to lose things at school and i'm not sure if phones are allowed in his school. But he feels so left out without a phone when everyone else has one.