Considering the average adult male thumb length is ~70mm and female is ~63mm[0], that would be 7-8% of thumb length increased in height and 4-5% in width. That

Considering the average adult male thumb length is ~70mm and female is ~63mm[0], that would be 7-8% of thumb length increased in height and 4-5% in width. That's not even including the very different screen interactions on XS vs the iPhone 8, where the screen itself was significantly smaller. [0] http://nymag.com/news/intelligencer/smartphone-thumbs-2012-9/ http://nymag.com/news/intelligencer/smartphone-thumbs-2012-9...