This Company Uses Earth's Magnetic Field To See Inside Buildings

In some ways, it's an ominous pitch. By measuring the "magnetic fingerprint" of any building in the world, the Finnish company IndoorAtlas can conjure up a startlingly precise indoor map of any building. It's technology that sci-fi has dreamt of for decades. But instead of surveillance, it's being used for shopping. »5/20/14 5:20pm5/20/14 5:20pm