NextGen gallery image approval system

Does anyone have any ideas about how you can share a gallery of images, a client can see them online and approve or disprove by clicking a box or maybe a thumbs up or down? I often send images I’ve upload into a gallery, but the only way for client to send me approved photos is by looking at file number. It would be a very nice flow if they could check a box or something and I could see that on a password protected page.

Is this possible? maybe in the .js effect when clicking an image or for the thumbs?

Thank you for reading,
RRG