An initiative called The Aphrodite Project has created GPS-enabled safety shoes for sex workers.
Each sandal will have an audible alarm system, which emits a piercing noise to scare off attackers. The shoes are also outfitted with a built in GPS receiver and an emergency button that relays both the prostitute's location and a silent alarm signal to public emergency services. Where there are problematic relations with law enforcement, i.e. most places, the shoes will relay the signal to sex workers' rights groups, such as PONY in New York, COYOTE in Los Angeles, or SWEAT in South Africa.
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