The mass shooting in Las Vegas this month was one of the latest incidents to draw listeners to apps allowing the public to listen to police and fire frequencies.
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Bug enthusiast Anna Lindqvist uploads photos like this — of the Ailanthus Webworm Moth (Atteva aurea) to the iNaturalist app. Like a social network for wildlife, her location paired with the photo help both amateur and expert naturalists identify the species.
There are countless communication options, including Yahoo's new Livetext app. Livetext allows users to send a message accompanied by live video but no audio.
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Susan Prescott, Apple vice president of product management and marketing, demonstrates the News app during the Apple Worldwide Developers Conference in San Francisco on Monday.
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After a tornado leveled Moore, Okla., last year, firefighter Shonn Neidel (left) developed an app that helps first responders locate storm shelters under the wreckage.
Courtesy of Shonn Neidel
Sandra Hassan put her app online in late January as yet more explosions struck Lebanon. She hopes it will help people in conflict zones, and areas hit by natural disasters.
Craig Federighi, senior vice president of software engineering at Apple, discusses features of the new iOS 7 during the keynote address of the Apple Worldwide Developers Conference on June 10 in San Francisco.