So it is likely the iPhone was in development for years before the Prada was even a concept.
An iPod phone, yes. The touch iPhone, no. As mentioned here many times before:
All the published iPhone histories, derived from interviews with Apple insiders, state that the current iPhone project began at the tail end of 2005, with the mobile OSX port (aka iOS) begun at the start of 2006.
In other words, most of the iPhone work was done in one year, which is very remarkable. Apple felt the pressure to rush to beat everyone to mass market. (If Apple hadn't done it, someone else eventually would've.)
You see, 2006 was a huge year of touch concept phones, from the actual Synaptics Onyx to the Nokia Aeon and Black Box concepts, right into the 2006 Linux based OpenMoko phone shown below with icon dock, multi-touch and pinch-to-zoom... ideas which some people thought were later ripped off by Apple for their iPhone.
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