New apps are helping smartphones to recognize images

"OK, this one is pretty cool," said 6-foot-tall Omar Tayeb as he held his left hand in front of himself and snapped it with his iPhone. He left it there as an app detected each of his fingernails and proceeded to paint each one. On the phone's screen, Tayeb's nails turned a dazzling shade of Maybelline purple. "So the app was able to detect where my nails were, paint them in one of Maybelline's nail polish colors, then adjust to the room's lighting so it looks natural," Tayeb said. And it is impressive, given that as little as five years ago the smartest smartphones would have struggled to recognize the most basic of images, let alone identify individual fingernails and accurately color them.