The FLEPia "colour e-paper mobile terminal" will initially only be available in Japan through online sales via the Fujitsu Frontech store.

Pundits were quick to criticise its 1.8-second screen refresh rate. US tech magazine Fast Company said: "Waiting nearly two seconds for the FLEPia to change its display is almost certainly going to get tiresome."

Deloitte media partner Mark Lee-Amies pointed to the book's slow transition to an electronic format, and said the device's high price point would be a barrier to uptake.

"One of the biggest socio-cultural challenges for consumers' adoption of digital books could be the public's profound affection for the conventional, paper-based book," added Lee-Amies.

David Taylor, president of on-demand book printer Lightning Source, said everyone knew the colour e-book would arrive at some point.

"Is the e-book going to be the death of the printed book? If I had a penny for every time someone had asked me that, I'd be a very rich man," added Taylor.

"The worst thing you can do is stick your head in the sand. How big e-books will be is anyone's guess, but they will have a place complementary to print," he said.

Lightning Source's sister company Ingram Digital distributes e-books.

The FLEPia costs ¥99,750 (£727) and will go on sale in Japan on 20 April.

Also see:
Amazon's latest e-book device gets mixed reaction
Ingram Digital signs e-book deal with Penguin Group