Imagine walking around with a 70 inch tablet.
your friend pulls out a 10 inch ipad, and you pull out your 70 inch tablet and put their ipad to shame.
it shouldn't be too hard, they can make a 70 inch display they can also make a tablet, why not combine the 2 and put a giant 96 cell li-ion battery to power it all.
You can add a ear piece and a mic and you now have a tablet that doubles as a cellphone, and they can also add sensors so when it is held to your face, the screen turns off then you can get weeks of talk time since you wont be powering a moderately sized 70 inch LCD screen