I'm not sure I want to lose the physical keys of a keyboard, but I'd be interested in trying a touch-surface sub-display control for navigation on laptops and desktops.
I'm not criticizing Apple's design choice here, but I would imagine that the trackpad would be a better natural location for it?
Nice spot for a file list to contextually appear, or a zoomed view from an image editor for example. They'd have to work out all the logic so the trackpad gave me the right display at the right time, and was easy to toggle, but it could be a nice addition to a laptop, iThink...
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