Application suitable to my need

There are no perfect guidelines or rules with regards in raising children into the world. They are attracted to fun, excitement, and activities that pump up their adrenaline. They are hardly equipped with the adequate experience to make rational and intelligent decisions. They often put themselves, their friends, and their parents into trouble. Our busy schedule and their privacy rights do not allow you to accompany them wherever they go, even though you often want to. In that note I really need an application installed on their mobile phones that I can monitor them while they are at school or with friends. Anyone here who can suggest a good app for mobile phones