How to find out what children are doing on their phone?

I use hoverwatch www.refog.com/hoverwatch.html to control my kids. Hoverwatch keeps information about incoming and outgoing calls, text messages, records phone calls and sends periodic reports about the phone’s GPS location. This program is easy to install and runs invisibly. I can find out where my children are and who they are talking to and about. With hoverwatch, all keystrokes are recorded on the computer. Each time a key is pressed by a user the program records that keystroke.