With Pocketbook, a couple Chinese companies, and now Onyx announcing a new device, 2020 has turned into the year of the color ereader.
Details are still scarce, but Onyx has officially announced that they will launch a color ereader this year. Well, they have not announced it so much as released this graphic, and said nothing else.
We do not know the screen resolution, price, or release date at this time, but this is most likely going to be a 6″ ereader, and ship some time this fall.
This device will likely be using the Kolaido E-ink screen tech announced by Pocketbook (the Chinese ereaders use the same tech, Pocketbook told me). That screen is capable of displaying 4096 shades of color at a resolution of 212 PPI, or grayscale at a resolution of 300 ppi.
Edit: Color screen resolution is unknown. Some sources say this screen tech can display color at 212 PPI, while Pocketbook says the screens going into their device have a color resolution of 100 PPI. (I trust Pocketbook.)
E-ink has not yet answered my questions about the difference in screen resolution yet, but one reader pointed out that the difference could be explained if the color mode requires 2 grayscale pixels to display a color pixel. If you look at the number of pixels on the screen (and not just the PPI), the math checks out.