PenTile screens have only half the total number of Red and Blue sub-pixels as the traditional 3 sub-pixel displays, so they aren't as sharp as traditional displays with the same pixel resolution and their highly advertised screen PPIs are not comparable. (displaymate.com)
The Nook Color uses a 7 ″ display with the same pixel resolution and it gets about 8 hours for reading, less for Android tablet stuff. (blog.the-ebook-reader.com)
It features the same pixel resolution as the larger iPad model on a smaller, 7.9 - inch display. (laptopmag.com)