Dark Alley? Call for Help

Use SafetyNet's map to select bad neighborhoods. Then, if you end up in a sketchy area, your mobile will switch into watchdog mode. If trouble arises, all you have to do is shake the handset and your phone will set off an alarm, start sending your location to friends and family every 30 seconds via Google Talk, take a picture, turn on its speaker, and dial 911 (or another emergency number) . The app announces each of these steps out loud so a would-be assailant can hear what's happening and give up.

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