20x per payment method. Could easily be abused beyond 20x per person

Most, if not all of the issues in the ESP8266 article were backend-related. If you create cheap hardware - you attract cheap software companies that use this hardware.

Camera's and LiDAR each have their pros and cons from a hardware and software (capability) perspective. But I agree that some of his tests could have used a bit more information on the 'why' rather than just saying it worked or did not work. It was a comparison of software vs hw and not hw vs hw

Always hurts when you see a "questions?" slide for 5min at a conference. Especially when they have to try and condense all knowledge in a 15min presentation.

And a nice timelapse :)

A "before" picture