Recently I was told by a developer that most 7 inch tablet users will, if given the choice (i.e the app supports both orientations), use the tablet in a portrait orientation and that a user with a 10 inch tablet will, by default, use the tablet in a landscape orientation. I've noticed that this is certainly true with my friends and family, however I was wondering if there is any research or statistics that actually gives a statistical preference, an extensive search of the internet hasn't provided anything yet other than a couple of articles about how many apps there are that have both orientations.
The question is somewhat answered by this post:
However, this doesn't address the issue of different sizes.
The devs at Google certainly seem to think this is true, their stock OS on a 7 inch tablet is geared up for it to be used in a portrait orientation whereas the 10 inch tablets come with a landscape set up as standard.