iOS used to be tied to a certain ergonomic form factor... a normal human thumb could comfortably travel the entirety of the screen while the device was held in

iOS used to be tied to a certain ergonomic form factor... a normal human thumb could comfortably travel the entirety of the screen while the device was held in the same hand. The latest iPhone has dimensions that make this uncomfortable for most people, and so these "sprinkled" buttons stand out all the more.