that seems to be showing the 'after' photos, can you see a before photo somewhere, to see the difference?

the link underneath directs you to the "before".

Ahh, I see.

I'm curious if they're using any learning algorithms here, where the computer 'learns' how to re-touch the photos. Or if its a more simple list of rules, i.e make these colors darker / brighter.

The learning happens on the level of seeing what would a human retoucher does by using the data we gathered from the editor: https://www.polarr.co/editor

That's very clever. Did you get in?

We got an invite. Thanks for asking.