i suspect what they're calling e-paper is something like the Sharp memory LCDs that Pebble smartwatches used, not the E-Ink that Kindles have. still very battery efficient; most of the power consumption from LCDs is in the backlight, not the actual display layer
It should go without saying but: do not buy this. Nobody has seen if the display actually looks like the promo videos, and the CEO is all over the crypto podcast space? highly sus, even if it'd be cool if true
When looking at that device, I feel like those dogs looking at roasting chicken in the street ovens, because as much as I'd love to have one of those, I know I will never be able to.
Back in 2016 I made an e-paper demo for a wearable medical device and despite a valiant effort there was a lot of ghosting and the refresh time was not impressive. I would imagine that this display is probably more power intensive but the impact that this tech could potentially have on the battery life of all types of devices with screens is considerable (and the main reason we were looking into e-paper displays in the first place)