Latest mobile phones available have Gps mapping effectively a sat nav this is a very convenient way of getting around without the need for a dedicated satellite navigation system reducing the need to purchase to systems. It can also be used to check where your children are so you know that they are safe and you can also check that they are attending school etc. This is something that is easy to setup and use they would not have to know that you are monitoring their activates, in fact it would be best not to tell them as they could easily give the phone to a friend to take to school. This new technology is not necessarily going to cost any more than your current mobile phone in fact with some of the deals at http://quick-call.2u.co.uk you might even pay less per month than you do now go straight there now and check