For example, Pico-8 gaming engine: https://www.lexaloffle.com/pico-8.php
and TIC-80 computer: https://tic80.com/
These are way too limited, but I could imagine something a little more powerful - 1024x768 pixel buffer, 64 MB ram and 100 MB space. All apps natively running on this (or even emulation) would instantly load and the latency would be unreal.
As a developer, I think the whole thing is so convoluted and asinine it should curl up and die in a fire. It will spawn an entirely new area of bespoke, non-maintainable yet critical business tooling.
On the plus side, they chose the environmentally friendly option, the alternative would have been disposable paper menus.
ESP-CAMs combine a 2-megapixel OV2640 with an ESP32 clocked at 240MHz that has a Wi-Fi b/g/n + Bluetooth 4.2 baseband integrated into the chip.
Finished/working flashable boards run for about $6 apiece on Aliexpress.
Compare that to the CueCat, which was made in 2000 and much more finicky about scanning: https://en.wikipedia.org/wiki/CueCat
I went to a restaurant tonight. Because of COVID-19, we were seated outside. Instead of being given a menu, we were told to scan a laminated QR code on the table. That loaded a website with the menu.
From one point of view, this is a huge waste of compute. The phone camera is scanning for QR code whenever it’s open, which is a waste. We’re calling up cell towers to do megabytes worth of downloading to get a website, when the text of the menu is at most a couple of dozen items.
On the other hand, the restaurant knew we’d have phones and didn’t want to either sanitize laminated menus or print and toss plain paper menus. You could imagine a system in the 80s where you’d use a CueCat style scanner to get a simple barcode for a text menu… but nothing was ever as widespread then as smartphones are now. The sheer ubiquity of computing makes it easy to solve a novel problem with overwhelming resources.