Remember that you are the adult, you have control. How old is your child? It is normal for him to cry, all small children cry if you take away their cell phone, but sometimes you have to be "the bad guys" it is for his own good, he cannot spend all the time he wants with the cell phone, there are limits to follow and it is for his well-being, it will not hurt him to cry for a couple of minutes, give him other options for activities such as painting or playing his favorite game