Turns out there is a "button" you can push on the side of the picture that turns the camera lights on and off. Picture is quite clear through the glass now with the lights off. :) (It is not dark like in my photo, which is at a bad angle for the iPad.)
Off tomorrow for a couple days up-Island between monsoons, so should learn how this thing works in real life. It is just to look out the back window same as the rear view mirror does; it does not replace the side mirrors. It does have a wide angle look out the back though so more view than the real rear view mirror would have. We'll see!
That 100ft out back view was just to the end of our driveway for the wifi connection test--could have gone farther, but you can see farther back. I will know how that goes once I get out on the road how far back you can see cars.
Yes, there must be a clever tech thing for boosting the wifi, but I don't know it. Ask a 13 year old! :)