Flexible Display from Readius

There is an interesting article on news.com, in which the author talks about Readius’ flexible eBook display:

“How can you balance the size of the screen so it’s big enough to read and reasonably watch videos, while keeping the device dainty enough to fit in a pocket?”

I do not see why eBooks need to be pocketable. What I personally want is an A4-sized eBook that is light, thin and that can contain all the books that I will ever own, in color, of course. By “Books” I mean magazines, manuals, brochures, news and so on… When I move around, I tend to read stuff on my phone and that is good enough for me. What do you think?