NB, "e-ink" is a special case of "e-paper". The terms "e-paper" or "electronic paper" tends to be a generic label usually applied to electrophoretic displays,

NB, "e-ink" is a special case of "e-paper". The terms "e-paper" or "electronic paper" tends to be a generic label usually applied to electrophoretic displays, though there are numerous other technologies (Gyricon, electrowetting, interferometry, plasmonics). E-Ink[tm] is a specific technology and trademark owned by E-Ink Corporation, covered by numerous patents, and to date has relied on electrophoretics. I've addressed display characteristics in another comment to this thread here: <https://news.ycombinator.com/item?id=39198053 https://news.ycombinator.com/item?id=39198053>. I can assure you that if e-ink characteristics and strengths are addressed by UI/UX design, e-ink can be quite satisfactory and is often preferable to other display options.