Not only was it truly mind-blowing at the time, but in retrospect, so much of modern computing was invented for that first iPhone phone and revealed to the world for the first time in that hour. Just watch the software demos: most modern UI mechanics and behaviors, large and small, began that day.
When it shipped six months later, it was possibly the best 1.0 in tech history, followed by a decade of relentless hardware and software improvements with the highest success rate and fastest advancement of any product line I’ve ever seen.
Regardless of modern UI design trends, we’re still living in the era defined by the first iPhone.