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  • Adam Witwer thinks this is interesting:

Here’s a tricky surprise: the one-handed thumb zone is smaller for phablets than for phones. As phone size increases, the thumb zone remains roughly the same shape and position—anchored to screen bottom—until the size hits a tipping point, where the grip shifts to stabilize the phablet.

From

Cover of Designing for Touch

Note

Makes sense since human thumbs aren't increasing to accommodate larger screens.