Fifty-eight percent of Americans own smartphones, and although 75 percent of all calls to 911 are wireless, most 911 centers today are still tethered to the voice-centered world of communications of the last century and are unable to receive text or photos.  There is a movement underway to move to a next-generation (NG911) system based on modern Internet protocol-based networks.  Here’s what you need to know about its development and implementation.