Many people have no idea what was cooking up in Apple's labs when the company was working on the iPhone, but a prototype from 2005 has appeared, and it features a roughly 8.6-inch display with a separate motherboard consisting of USB ports, ethernet, and even a serial port. It was the basis of what iOS devices came to be a couple years later.
Ars Technica ended up getting an exclusive look at the old prototype, and it essentially looks like a miniature table. Of course, the late Steve Jobs actually thought of the iPad first before the iPhone, so this actually could be an iPad prototype that was used to eventually make the iPhone that released two years later.
The photos come from a former Apple employee who says that "at that early date no one knew what [the final device] would be." The prototype is roughly two-inches thick, so you definitely wouldn't be able to slide it in your pocket or bag with ease, but the former Apple employee says that it was "really impressive seeing basically a version of OS X running on it," during that time.
It should be noted that the chip that the prototype is running is the Samsung S3C2410, which is "a distant relative of the chip the first iPhone ended up using, just older and slower." The prototype chip was clocked at around 200-233MHz, while the first iPhone used a 620MHz chip underclocked to 412Mhz. We've certainly come a long way since then.
[via Ars Technica]