Feature the iPhone needs to stay ahead of rivals
Many rumors point to the next high-end iPhone as something special, or at least exceptionally considered even by Apple standards. These include hints that the new smartphone will boast a nearly bezel-free design highlighted by an OLED display and that it will include camera enhancements that make it a better match for ARKit. One might quibble if Apple goes its own way with wireless charging. But if that comes with some benefit such as dramatically improved range, loyalists likely won't complain much.
However, one decision that could be more divisive is whether to hide or remove the Home button. Despite the iPhone's popularization of its multitouch screen, the Home button was a defining part of its user experience, leading it to be known as the "one-button phone" (not strictly true, given the volume controls). Even as Apple introduced multitouch gestures to make it redundant, the Home button evolved from a critical interface reorientation device for neophytes to an activation point for multitasking and Siri as well as the home for Touch ID (which cost it the rounded square on its surface).
The Home button's removal would not only be in keeping with Apple's general trend toward the elimination (or at least replacement) of components but also its specific crusade -- now joined by its competitors -- to optimize screen-to-body ratio. After all, when the iPhone was introduced, Steve Jobs decried the lower half of contemporary smartphones such as the BlackBerry and Palm Treo for their thumb keyboards that are now all but extinct. In the iPod era, Apple itself long had a device that sacrificed screen area for control area, including one model that had completely forsaken the former for the latter. However, with the iPhone capable of so much more than the iPod, flexibility became paramount.
As other handset makers have tried to extend screens to the edges of phones, companies such as LG have had to move their home buttons or at least the fingerprint readers that the Home button doubles as on the iPhone. They have generally been reoriented to the back of the device and can usually be activated pretty effectively with a little index finger muscle memory.
Of course, the rich variety of Android handsets provide many case studies. Locating the Galaxy S8's narrow, off-center fingerprint reader on the device's back can be frustrating, particularly when one is switching off between left and right hands. Meanwhile, Lenovo has stuck with a more traditional aspect ratio with the Moto Z. Its latest iteration not only keeps the home button/fingerprint reader below the screen but accommodates clever gestures. Swiping left activates the back function while swiping right activates the recent apps function.
But, of course, the former has no equivalent in iOS. Apple is unlikely to move the button/reader to the back given it tends to adhere to ergonomic decisions such as where it should have been placed originally.
This far into the iPhone's history, there are fewer people in its addressable market that would need to rely so heavily on the visual cue of a physical Home button, Nonetheless, Apple would ideally devise an option that preserves the discoverability of the Home button and Touch ID. While future iPhones may support other authentication methods that require less room on the device's surface, fingerprint reading has proven worth maintaining even with the addition of iris scanning and other authentication technologies.