Things are beginning to make sense...
There's been a lot of discussion of the different size touch screens for a tablet; the necessity (or lack of) a full QWERTY kb; and the OS (iPhone OS X vs Mac OS X).
Previously I posted that a pack of 3x5" index cards was about the right size for a device with a 6" diagonal (approx) display that would slip into a shirt or pants pocket. This size would give a 800x480 pixel display if it used the iPhone resolution of 163 ppi.
But it would still have a smallish touch screen kb.
Now look at what Nokia is doing with this [display] size:
http://www.electronista.com/articles/09/08/19/nokia.n900.reviewed/
By enclosing the 800x480 display in an expanded case they have allowed room for a slide-out QWERTY kb. Whether this is full-sized or somewhat under-sized is difficult to tell. And while you may be able to stuff it into a pocket, it appears very bulky.
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Then there were discussions about a larger, say, 10" diagonal screen size. Someone posted that folding an 8.5x11" sheet of paper in half yielded a surface that would support a screen with an (approx) 10" diagonal.
For comparison, I have a hard-copy of Grisham's book "Bleachers" which is just slightly larger and about 5/8' thick... a very comfortable size. It is a nice size display for reading (books) and easily supports 16:9 or 16:10 video. While it wouldn't fit into a standard pocket, it would nicely handle a full-sized QWERTY kb on the display (move a few keys).
So, maybe, this size solves a lot of user needs/complaints for a full-sized kb.
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Then there is this:
http://www.macnn.com/blogs/2009/07/29/stunning-nano-phone-surfaces-in-patent.html
If I understand this correctly, it may offer the best of both worlds for a tablet:
1) front surface, full-screen touch display with capability to type or draw with fingers or stylus
2) back surface, full surface touch area with pressure sensitivity and haptic feedback.
I wonder how feasible it would be to hold the device, by the edges, with 2 your palms and touch type with your thumbs and fingers, on the back.
Grab a copy of Grisham's book and try it!
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Oh, and you could have something approximating a full-size QWERTY kb on the back of that 6" tablet... or even the current-size iPhone.
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