Lots of visual space makes processing text easier for a subset of dyslexics.
In a paper published in the journal PLOS One, the authors found that a group of dyslexic teenagers showed greater reading comprehension when using an iPod Touch e-reader than when asked to read from paper. The e-reader was formatted to display around nine lines of text on the screen at a time, with only two or three words in each line, leaving fewer visual distractions. The authors therefore concluded that this improvement is due to the reduced demands on visual attention when reading from the iPod.
Via Dennis T OConnor