Ming-Chi Kuo, an analyst with KGI Securities, believes the model that will follow what many believe Apple will unveil on Wednesday will be much thinner than the iPhones we know today. The iPhone 6s, as it’s believed to be called, will be 7 millimeters thick; the so-called iPhone 7 could be as thin as 6 millimeters.

Sounds like splitting hairs, I know. But there are some interesting design (and supply chain) challenges with such a prediction.

Apple’s move to what it calls “Force Touch,” a virtual input method that mimics the “give” that a physical button has when pressed, appears to be at the center of the change. Applied to a smartphone, Force Touch could allow for an iPhone display that is pressure-sensitive. That’s a fairly dramatic shift in terms of how the iPhone is designed and constructed, even though many users won’t give it much extra thought. (As my colleague Philip Elmer-Dewitt called it: “The iPhone’s next big thing.”)

And it may change the way phones are built moving forward. According to Kuo: “Apple and its suppliers have invested heavily in iPhone Force Touch in 2015 and we believe 2016 new models will stick with a similar Force Touch structure as used in 2015.” (AppleInsider first obtained Kuo’s research note.)

There are many questions to be raised about the move to a thinner design. Concerns about bending and flexing certainly remain an issue. The ability of manufacturers like Foxconn to build durable phones with ever-smaller clearances and expected performance is also a consideration—remember the Great White iPhone Challenge of 2010, the result of light leakage through its face?—though Apple has done wonders to reconfigure the inside of devices to result in diminutive profiles. (See the latest Macbook.) And the rise of wearable electronics, such as Apple’s own Watch, is teaching equipment manufacturers how to balance performance and power consumption in increasingly cramped confines.

The next next iPhone, like those before it, will be thinner, lighter, and faster. So will Samsung’s next next Galaxy I’m certain. To consumers, it sounds like a snooze. But to keep rethinking display, battery, and input technologies with every release? It’s a testament to how competitive and exciting the business of smartphones continues to be.

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