Amazon leads the e-reader market with 51.7% share, ahead of Barnes & Noble's 21.2%, according to IDC.

The e-reader market has shifted with the iPad.

But we've also suggested that the iPad is responsible for killing the e-reader market for everyone but Amazon and, to a much lesser extent, Barnes & Noble.

But this is a different kind of "death by iPad" than what the e-reader market has suffered-it's more like the difference between involuntary manslaughter and first degree murder.

If they do so, they will have more appeal to university students and instructors, a major, under-served e-reader market.

In 2013 ABI Research found that the decline in the e-reader market was due to the aging of the customer base.

And, given that nearly the entire e-reader market seems dependent on a single display provider in one form or another, it's good to have options.

The Kindle is Amazons grand entr into the e-reader market.

Faced with growing competition in the e-reader market, Amazon has redesigned the device and has made it available directly from its UK site for the first time.

Kindles are estimated at 50-70% of the e-reader market, depending who you ask (since they don't release sales figures).