Then again: last year Apple filed a patent for a next-generation periodical reader with a flexible display. So maybe we'll be seeing Apple devices so thin they could give you a paper cut.
Perhaps the most fascinating part of this issue is how Apple's drive for technological advancement inevitably clashes with our own biology. Human bodies haven't changed much in 200,000 years. Our eyes are imperfect and get worse with age. Our hands come in a limited range of sizes, our fingertips are small, and we only have so many fingers.
In the end, maybe the Apple Watch (which has quite a bit of room to get thinner itself!) suggests a different way forward, with smaller tech products scattered everywhere. Once there's a touchscreen display and microphone on your wrist, and a tiny wireless speaker in your ear, and a thin-but-not-too-thin iPhone in your pocket, measuring and weighing every separate component of that constellation of devices might seem completely unimportant.
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