eink responsiveness itself: it's "slow", but much of it is in software. the remarkable demonstrates that pretty well - pen-to-display updates in ~20ms, which i

eink responsiveness itself: it's "slow", but much of it is in software. the remarkable demonstrates that pretty well - pen-to-display updates in ~20ms, which is more than fast enough. for further evidence, dasung's eink monitors are stunningly fast because of good software (and surrounding hardware that can drive it all) - they use the same panels as others AFAICT. (i.e. they're using the standard high-end e-reader panels. there are dramatically slower and more limited panels designed for signage, I think we can ignore those - many don't even have partial update support in their hardware) The caveat there is that those fast updates are for black to white or white to black - gray to gray is slower, and accumulates error if you keep doing it (ghosting). remarkable has built their entire UI around this limitation: all UI is black/white, no grays. All tools (except the highlighters) draw black/white, no grays - all the texture is just black/white pixellation patterns. a lot of care has gone into working with the hardware's limitations at every level.... which is something android will never do. other causes of latency often include stuff like aggressive CPU sleeping to make the batteries last weeks. if you get rid of that, and pre-render the next screen, changing screens is something like 100ms or less. in the end you have a pile of tradeoffs that generally mean worse user experience when poking the device to get better user experience somewhere else. which is true of everything.