Concerned parents—or vigilantes—with an iPhone can download a new set of applications that track crime, list fugitives, or even pinpoint the locations of freed sex offenders. Using public records, developers have built programs like Offender Locator, which uses the phone's GPS to identify homes of nearby felons, complete with photographs. Offender Locator has been downloaded 1 million times, though public interest advocates warn the app's information can be inaccurate.
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