Need to find research on the psychological impacts of smartphone use, specifically in the United States/Canada/(insert country of Western power here) between 2007 and 2017.
Reading about the "melting" of the device as an appendage makes me definitely believe this is by design (and we'll never get that information from the companies directly: that's like Microsoft opening source NT tomorrow or Apple open sourcing everything under a MIT license).
I know about the "pinky finger" adjustment that my generation and later have now adjusted since we're given these things so young that there's a dimple in one's pinky (due to prolonged use of holding in one's hand).