So what can smartphones not do? In Japan, you can buy a vendor meal. In the U.S., some phones can open doors for a level of access control. The U.S. Department of Homeland Security (DHS) is studying a plan to plant radiation detection into consumer phones so that they call to indicate the coverage of a dirty bomb attack.

And now there is an iPhone app to alert to deadly chemicals. Scientists at NASA’s Ames Research Center, working with DHS, have created a portable chemical sniffer. It’s about the size of a postage stamp, can plug into 30-pin dock connectors, and can quickly detect airborne traces of ammonia, chlorine gas, and methane. The device senses chemicals in the air using a “sample jet” and a multiple-channel silicon-based sensing chip, which consists of 16 nanosensors, and sends detection data to another phone or a computer via telephone communication network or Wi-Fi.

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