Out comes the motherboard, with three little cameras in tow.

Front and rear cameras are familiar fare on smartphones, so what's the third camera for?

That would be the Note7's trick iris scanner. It's actually a two-part system: a nearby infrared blaster invisibly lights up your eye, while the sensor captures an image that's said to be more secure than a fingerprint.

For comparison we have the iris scanner (right) with the Note7's 5-megapixel, ƒ/1.7 selfie cam (left).

And for the X-ray comparison, here we have the two cameras still in the device.