The Hisense A5 was unveiled last year with an e-Ink display. But that was a monocrhome screen, this year the company is showing off a new prototype phone with a color e-Ink phone at CES 2020. Details are scarce at the moment, but the new display reportedly features improved contrast and refresh rates compared to the panel on the A5. That said, color e-Ink screens tend to have much slower refresh rates than the already slow monochrome screens, which isn't an issue for an e-reader, but is really limiting when it comes to smartphone UI. A prototype of smartphone with color e-Ink...
Source: https://www.gsmarena.com/hisense_demoes_phone_with_color_eink_display_at_ces_2020-news-40962.php