Reading an ebook is substantially slower than reading a standard paper version, according to a study.
While Jakob Nielsen of the Nielsen Norman Group only looked at 24 users, the difference in reading speed between the electronic devices and the printed book was noticeable enough to be just about statistically significant.
Each participant read a short story by Ernest Hemingway on each of the devices. Nielsen found that those using an iPad were 6.2 percent slower than those reading a standard book, and the Kindle 2 was 10.7 percent slower.
Nielsen also asked his guinea pigs how happy theey were with their reading experience, rating each device out of seven. Here, the iPad, Kindle and book all fared much the same, at 5.8, 5.7 and 5.6. A PC did substantially worse, with a usability score of 3.6.
"Most of the users' free-form comments were predictable," says Nielsen.
"For example, they disliked that the iPad was so heavy and that the Kindle featured less-crisp gray-on-gray letters. People also disliked the lack of true pagination and preferred the way the iPad - actually, the iBook app - indicated the amount of text left in a chapter."
The reason for the unpopularity of the PC, says Nielsen, was that it was associated with work. The paper book was seen to be more comforting than the alternatives.
Nielsen believes the study is encouracing for the takeup of ebooks and tablet computers.
"We can expect higher-quality screens in the future, as indicated by the recent release of the iPhone 4 with a 326 dpi display," he says.
"But even the current generation is almost as good as print in formal performance metrics — and actually scores slightly higher in user satisfaction."
In a survey conducted immediately before the launch of the iPad, research from ChangeWave found that more than a quarter of e-reader owners said they'd have bought an iPad instead if it had been available.
And 40 percent of people who said they planned to buy an e-reader in the next three months said they were opting for an iPad.