Looks like it's running a pretend-terminal website which probably explains the latency (the Kindle does not have a fast processor).
Way on the other end - here's a Dasung 13.3" eInk monitor (i.e. you feed it DVI and it handles all the display driving for you). It can be yours for a cool $1000. I'll pass, but it's looking pretty good even for GUI usage. Probably uses more power than a purely embedded solution could, though.
FYI, I've seen virtually zero latency running livereload experiments with the embedded browser in my Kindle, the basic 3rd-gen 2014 model.
My method was extremely rudimentary - inotify -> long-polling JS (being fed entire new file) -> innerHTML rewriting, with the Kindle connected over 802.11g - but hitting Save in my editor produced updates on the Kindle's display in around around 20-40ms.
I would put a moderate amount of money on the possibility that the latency is coming from the fact that the terminal app in the video is being run on a non-local server, and that keystrokes have to go up to the cloud-hosted app and then come back down to get onto the Kindle's display.
If the whole thing were local (with the terminal app hosted on target system, ideally) I expect updates could happen in <100ms.
Also, the CPU is a 1GHz i.MX6 (@ 996MHz), next to 400MHz LPDDR2 (@ 396MHz). It performs quite well in my experience; it's the OS that's terrible. :P
(The best OS I've yet seen was the one on my Ericsson MC218, which let me drag windows around the display faster than the LCD crystals could physically keep up. Solid windows, not outlines. On an ARM7TDMI running at 36MHz.)
https://www.youtube.com/watch?v=ymei7UwBgX4
Looks like it's running a pretend-terminal website which probably explains the latency (the Kindle does not have a fast processor).
Way on the other end - here's a Dasung 13.3" eInk monitor (i.e. you feed it DVI and it handles all the display driving for you). It can be yours for a cool $1000. I'll pass, but it's looking pretty good even for GUI usage. Probably uses more power than a purely embedded solution could, though.
https://www.youtube.com/watch?v=vny-JTpt-aU