A teenage tracking system has been developed to help parents locate their offspring without embarrassing them with a phone call in front of their friends.
KidsOK establishes the location of a child with a mobile phone within 60 seconds.
Parents "ping" their child's mobile by sending a text message to 60777 including the child's name.
The system, which uses global positioning technology similar to that in cars, identifies the position of the child to within 500 metres in built-up areas. A text description and map of the location is then sent back to the parents' phone.
The service is endorsed by leading children's charity Kidscape.
Richard Jelbert, head of mTrack Services, the company behind KidsOK, said: " Receiving an embarrassing call or text message from your mum or dad wanting to know where you are is the last thing kids want when they're with friends.
"Now they can use this service to discreetly 'ping' their child instead of calling or texting."