I am pretty sure I am not the first one to think along these lines, so I am seeing if anybody has heard any announcements along these lines from hardware companies, as I would be very interested in this kind of setup.
Basically, what I have in mind is a sort of bluetooth-connected phone, with a minimal screen and numberpad that would be paired with a tablet with voice capabilites to act as a real phone while the tablet is tucked away in a bag or pocket. So basically you could treat it as a phone, while the tablet is actually doing all the work.
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