Last year a security firm in the UK launched the Mosquito, and auditory device that emits a sound that can apparently only be heard by teenagers.
The Mosquito ultrasonic teenage deterrent is the solution to theproblem of unwanted gatherings of youths and teenagers in shopping malls and around shops. The presence of these teenagers discourages genuine shoppers and customers' from coming into your shop, affecting your turnover and profits. Anti social behaviour has become the biggest threat to private property over the last decade and there has been no effective deterrent until now.
Now it appears the very same sound has been hijacked and turned into a ringtone that only teenagers can hear.
Techno-savvy pupils have adapted the Mosquito alarm, used to drive teenage gangs away from shopping centres.
The alarm, which has been praised by police, is highly effective because its ultra-high sound can be heard only by youths but not by most people over 20.
Schoolchildren have recorded the sound, which they named Teen Buzz, and spread it from phone to phone via text messages and Bluetooth technology.
The sound relies on a medical phenomenon called presbycusis, where some hearing loss occurs related to age.