Helio, the US MVNO jointly owned by Earthlink and Korea’s SK Telecom, launched a GPS tracking service on Wednesday that allows subscribers to keep tabs on their friends.

When Helio members switch on their ‘Buddy Beacon’ the GPS satellite technology broadcasts their location to the friends they have added to their Buddy List, showing their location on a map.

Members can add up to 25 Buddies to their Buddy List and can send out an SMS message asking their friends to flip on their Buddy Beacons.

Users can just as easily turn their Buddy Beacon off should they not want to be located, which may come as a comfort to parents as Helio targets the youth market and has a partnership with MySpace allowing the networking site’s 55 million users to read and blog to the site from their handsets.

In addition, Helio is also launching Google Maps for mobile with supporting GPS capabilities, allowing them to pull up a current location on a map and get real time traffic reports, directions, integrated search results and satellite imagery.