7" should be more portable. Ideally, it should have micro phone, GPS, and 3G network, and camera. It also should be able to handle 720P video. Amazon should do add those, even for $50 more(total will be $250) device. People will buy it. Now less people will buy it because 7" is too small to use at home or office. It's portable but it doesn't have all the features for a portable device.