Now you don't have to give up the convenience of your iPhone to produce more sophisticated Facebook Live video. An update to the's app in early 2017 will let that add-on camera for the iPhone support live-streaming to Facebook.
The One has a 1-inch imaging sensor, much bigger than that in the iPhone, which helps it deliver better photo and video quality. But its biggest trick here is the new multicamera-switching capability, plus the ability to use all three available cameras at once: the iPhone's front and back in addition to the One. You'll be able to monitor the streams and switch cameras with a touch. You also have the choice of which microphone to use.
Combined with the Wi-Fi remote capabilitiesand the ability to operate while charging, it seems to be a pretty compact live-streaming solution. And it theoretically will work with models back through to the iPhone 5.