HP OmniGo 700LX, pdQ, and Nokia 9000 Communicator didn't have touchscreens and were like night and day compared to either the Prada or iPhone. You are comparing apples to oranges.
Was it a nice industrial design? Yes. Wasn't very original though (and neither was the iPhone's).
You're also shifting the goalposts - you said smartphone, not "had a touchscreen". It was the first capacitive touchscreen but not even close to the first touchscreen btw. The IBM Simon in 1992 likely takes that win.
What the iPhone did that was innovative was in how it improved upon and combined the technology. It also pushed forward a lot of things in those technologies by several large leaps.
Long story short - the LG Prada is superficially visually similar to an iPhone and, likewise, bringing it up shows a very superficial understanding of the history of the mobile phone space.
Android, Windows phone, and iPhone all added these core features.
But that would be silly, because the modern "smartphone" era was absolutely started with the iPhone.