Mobile phones keep children safer, as it is easier for parents to stay in touch with their children. Through calls and texts, parents can know where their child is and be reassured that he or she is safe. And in an emergency, young people can summon help quickly.

yes i do support them having cell phones but with age

My eldest son is 12 and has his own cell phone on my plan. He understands his minute usage allowed and only uses it when it is free, after 9pm. Addtionally his cell phone has a child locater feature on it, the reason i brought that model, and I can locate him anytime I need to.
His cell phone also has zones set up, one for home and one for school so whenever he travels outside the zone or moves from home zone to school zone I am sent a text message alerting me. This has saved me many heartache moments when he is not at home on time because the bus is running late or he is goofing off.
I can log into my computer or log in thru my cell phone and get an exact street address for him.
I can check to see who he is texting and what time he is texting. . . . .I have caught him a couple of times texing after he is supposed to be in bed.
Addtionally I can restrist his phone to incoming calls only and block numbers from people I dont want him talking to.

I think if used properly cell phones can be an addtional tool that parents can use to monitor thier children.

yes, with rules(n punishments also) which r non-negotiable,