Melbourne, June 3 (ANI): A mobile phone tracking device that could help you trace your family and friends has been launched in Britain.

The device delivers a map to the inquirers mobile phone, giving the location to the nearest 100 metres.

However, the service providers insisted that such a technology could only work if the person being sought allows to be traced.

In case someone has already agreed to be tracked, then they also have an option to be made invisible for as long as they want.

Users will be able to register on the Social Network Integrated Friend Finder (SNIFF) though social networking sites Facebook, Bebo and MySpace, as well as online, and each searching text will cost 50 pence.

American-based company Useful Networks, the service provider, is hoping that hundreds of thousands of people will sign up for the device.

The technology has been running in Scandinavia for several months and each registered person has an average of five to seven people they track.

You are fully in control of who can track you and when, you can go invisible any time - that is paramount, News.com.au quoted American CEO Brian Levin, as saying.

This service is for people you have a trusted relationship with - people you give your car keys or the keys to your house.

The most asked question on mobile phones is ‘where are you? and there are a lot of cases where you dont want to answer your phone because it is too loud or have the hassle of texting.

The value is being able to answer automatically, but it is not going to replace calling or texting, he added. (ANI)