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1 .This is Scientific American's 60-Second Tech. I'm Larry Greenemeier. Got a minute?
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2 .Touch your smartphone screen and you local weather or a street map.
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3 .So you might assume that mobile phones know exactly where you are.
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4 .But get into trouble and you might find your phone isn't watching you as closely as you thought.
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5 .Emergency responders recently told the Wall Street Journal that their 911 dispatchers have trouble getting help to the location of cell phone callers.
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6 .And a report this summer showed more than half of all California wireless 911 calls in certain areas didn't have location information.
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7 .One way to locate a cell phone is through GPS, assuming the phone has one and it's outdoors.
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8 .Another is through location-based services.
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9 .These follow the signals sent between your phone and your wireless network's radio towers.
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10 .But towers can be miles apart, making it hard to pinpoint locations and adding minutes to response times.
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11 .Responders want wireless companies to include location data with each call, something privacy advocates oppose.
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12 .It's a matter of perspective.
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13 .Sometimes you want to be off the grid.
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14 .But in a crisis, the grid could be your best friend.
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15 .Thanks for the minute, for Scientific American 60-Second Tech. I'm Larry Greenemeier.
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