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iReader Smart X3 is the first E Ink tablet with a Carta 1300 display
(liliputing.com)
For all things ereader
Contrast is huge if you read books at night in white text on black "night mode" too. That's how I do almost all of my reading now and I'm not particularly satisfied with the contrast on my Carta Plus reader.
Current tech is a bit like reading white on black newsprint, the contrast just isn't great.