The next mobile imaging war won't be waged over megapixels

For the past several years, improvements in smartphone cameras have followed the "more megapixels" mantra. Samsung's Galaxy S5 is up from 13 to 16 megapixels; Sony's new Xperia Z2 packs a 20.7-megapixel Exmor model; and Nokia's Lumia 1020 with...