There was "mirasol" which was full color high refresh rate passive display technology.
It is unclear to this day why it never made it to market considering that E-Ink is a far inferior product.
It is unclear to this day why it never made it to market considering that E-Ink is a far inferior product.
The short of it seems to be that production runs of Mirasol panels had very high fault rates, which lead to delays and losses. Qualcomm ultimately decided to abandon it and to fully focus on the Snapdragon processors which were perfectly aligned with the booming IoT space at the time.
Mirasol was apparently very promising and ahead of its time, albeit immature. It was based on electro-mechanical mirror pixels rather than dye. The biggest technical downside seemed to have been that the colors were pretty washed out and bland.
EDIT: It actually did make it to market. There was even a smartwatch powered by Mirasol (the Toq). It was never implemented by the big e-Reader brands though.
It does look good in the comparison you linked. It is being backlit though, while the E-ink is not. Maybe the mentioned blandness is more of a problem when used fully passively.
It seemed to have been a good competitor regardless, and it's sad that it got mothballed.