Some people here aren't seeing things from their children's perspective. Look back at your own childhood and determine everything that your parents did to raise you whether right or wrong and how you reacted from it. At age 10, I already knew at least a little about the birds and the bees (with bad advice from my older brother) and had a computer in my room. In middle school, I already knew about predators and pedophilles both online and in the real world. Around high school was when I had a decent smart phone that wasn't used or parental controlled.
Apart from a few hiccups, I manage to not be addicted to porn, not be a bad influence, and not get assaulted sexually. I'm about to be a college graduate and starting a very happy relationship with someone. Not to shabby considering I was past back and forth between aunts, uncles, schools, juvy, churches, etc before I actually lived with my mother. Heck, I'm having to teach my grandparents how to be responsible online sometimes.
You can't put your kids in a box their entire life. They have to learn from their mistakes and figure out how to get out of the situations you are afraid they are getting into. Otherwise, they won't make it out there. As a parent, you have to provide guidance.