Ever since Amazon released the popular Kindle electronic reading device, other software developers have been frantically working on their own version to grab a slice of the market.

As Apple gears up to release its own version, with e-books accessible through its iTunes store – and Google is also expected to follow suit later in the year – publishers, authors and readers will be spoilt for choice.

The true value of an electronic book is still yet to be fully determined with Amazon setting its prices competitively and publishers working hard in negotiations to secure the best deal. Their positions could be strengthened somewhat with the introduction of Apple, and so a royalty terms battle is all set to commence.