Needs to be clam-shell dual-screen like the Sony S2 (on the inner sides of the shells) and needs the outer shell to have a basic screen and some real buttons (for phone only use).
The outside should be made very similar to the forever classic and desirable Nokia 6310i. The 6310i is the best 'feel in your hand, use with one hand, not need to look out it while you are dialing' phone ever built.
Come'on Nokia. Keep the best of the classic and move forward and innovate at the same time. You had the best phone ever. Now merge it with the smartphone concept without losing that real phone feel. Just stuff the dual-screen computer displays on the inside.
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