Anti-Loitering: Ultrasound

全球警察和地方当局使用的反游荡技术！

The app sends out irritating ultrasounds that only young adults and teenagers can hear. After a while the sound will become so annoying that they will have to leave the area or won’t even come near you.

This technique is already used as an repellant by police and local authorities worldwide to reduce anti-social behaviour among teenagers, such as loitering youth, vandalism, drug use, drug distribution, and violence.

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MEDIA:

An estimate of more than 3500 councils, shop owners and police in the USA are currently fighting loitering youth with high frequency (ultrasonic) devices, also know as mosquito boxes. The technique has also has won the Innovation Prize Police ( PIP ) in 2006.

Wiki: https://en.wikipedia.org/wiki/The_Mosquito

Our app offers the same technique now for your mobile phone, and because of the portability you can use it on the road, trains, subways, or at the park.

Turning on the high frequencies sounds will make the area around you unattractive to teenagers without causing discomfort to adults. The sound of the app can almost exclusively be heard by young people till around 25 years.

HOW TO USE:

The app has six different high frequencies: 14 , 15 , 15 , 16 , 17 , 18 , 20 KHZ . Depending on your age and the condition of your hearing it's possible that you can still hear some frequencies. Only turn on the frequencies that you can not hear.

RANGE:

The effective range is dependent on your phone's speakers. Tip: Connect your phone to an external speakers for more range.