It looks like a mount for the phone, which is supposed to use its camera to act as an optic. Camera sees scene, their app overlays a crosshair image, you zero by moving the application's crosshair on the phone.
Meaning, of course, that it is a $129 plastic weapon-mount clamp for a phone that isn't rated for recoil.
More impressive would be a shock and recoil-proof camera/scope that mounts on the weapon that you could mechanically zero and tie into your phone/screen/whatever via Bluetooth 4. But that isn't what this is.
If you're facing a moving target. or are moving yourself, I wonder how much the camera's latency may affect accuracy? The camera lags behind the action. It's worse with my iPhone 4S than my new iPhone 6, but it is still noticeable.