This test opens the back camera and checks the framing live, as the customer photo screen will: step back, too far, too dark, two faces. Then it keeps 7 frames around your tap and finds the sharpest.
Ask the person first. Nothing is saved or sent: the pictures stay on this phone. Only the checks come from Google, about 11 MB, once.
The phone will ask to use the camera: tap Allow.
3 before your tap, 3 after, and one full photo where the phone allows it. The number under each is its sharpness over her body: higher is sharper.
Nothing was saved or sent. Going back to the camera clears these frames.