Came here to say something similar about touchscreens on phones. It's probably the most impactful innovation they've had, and ever will have imo. I can't ethically support Apple as a company and I haven't owned an apple product since the first iPod touch, but they absolutely deserve credit for this one.
Even if they didn't invent the touch screen, or even the touchscreen phone, they certainly figured out how to perfectly integrate touchscreens into mobile devices a fluid and intuitive user interface which served as a canvas on which to build pretty much anything you wanted in the form of a mobile app (a $200B+ industry which the iPhone absolutely catalysed the explosive growth of).
It arguably even began a significant change in the course of modern human interaction, due to how much more versatile and therefore more commonly used mobile phones with a similar UI basis became since then; because of that, increasingly popular social media platforms now had a new way to provide use for their platform (via mobile apps) on a device that pretty much everyone now had with them all the time. I don't think it's coincidence that social media use saw such substantially explosive growth soon after the iPhone and subsequent "copycats" were on the market.
So their innovation here was really the first step in a number of global paradigm shifts. It was just such a monumentally impactful step forward. Because of this I genuinely think that the iPhone is almost guaranteed to be in history books for centuries, like the printing press or the light bulb.
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