Earlier this week Panasonic posted a video which shows a shelf label prototype which can be powered by the smartphone used to update the label.
Now if only Panasonic could come up with a better use for it.
The whole point of electronic shelf labels is that they are supposed to save labor costs by being updated remotely from a central transmitter. Panasonic's prototype defeats that idea because it requires that a person wave the smartphone over each label. That's takes time and labor, and for what, to save battery life?
That's not a good trade-off, but that is less a problem with this idea than with Panasonic's prototype. Hopefully they'll adapt the idea for other uses.