This is a great article about the most central part of the iPhone/Pad. For the foreseeable future, the home button will remain (albeit the years of changes, fit and finish) as long as the size and UI (not solely gesture-based yet) paradigm stays the same.
Have a read at the breakdown from first to current gen hardware and the upgrades and changes that ensured.
“We are now six years into the iPhone 5 product cycle and quickly approaching a seventh iteration, yet Apple keeps repeating the same mistake when it comes to the Home button. It’s too early to tell if a metal shield and a bit of yellow tape will solve past woes caused by the Home button when it comes to the iPhone 5, but my gut tells me that the answer will be no. In the mean time, iPhone 4S Home button issues are starting to rear their ugly heads…”
The iPhone Home button: A look at how it has evolved, and where it still needs to go | iMore.com.
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