Earlier this year, Polymer Vision announced its combination mobile - phone / e-reader baptized Readius, featuring a flexible 5 - inch, 16 -
grayscale electronic -
paper display that rolls up into a handy 115x57x21 millimeters in 115 grams.
The Nook Wi - Fi dons a 6»
electronic paper display with 16 level
grayscale and adjustable text size, all specifications that describe Amazon's rival reader, the Kindle 2.