Check out This Video of Apple’s Early iOS Prototypes Going Head-to-Head

Remember earlier this week when we learned how, long before the iOS we know and love today was even a marketable platform, Apple had been working with that rudimentary build of iOS — dubbed ‘Acorn OS’, internally — that was configured around a virtual, click-wheel interface?

Well, According to Sonny Dickson, the famed serial leaker who initially confirmed the existence of ‘Acorn OS’, the prototype he showed off on Monday wasn’t the only pre-iOS prototype he had to show us. In addition to the ‘Acorn OS’-powered device, which is dubbed (P1), Dickson shows us in the video below a device referred to as (P2) — a similarly designed, candy bar-style handset running a noticeably more advanced pre-iOS build. As you can see, the (P2) device cooers to be decked-out with some relatively modern icons, although the software is still not the original, commercially available version of iOS 1.0.

Dickson wrote how he believes the more advanced software running on the (P2) device was originally designed by Scott Forstall — Apple’s former Senior Vice President of iOS Software who, during his tenure working for the company, was largely responsible for the original development of iOS for both iPhone and iPad. Interestingly enough, when you view the two devices, side-by-side, it becomes remarkably clear why Apple ultimately decided upon Forstall’s more minimalist, streamlined interface — as opposed to what Dickson believes is the Tony Fadell-designed, iPod click wheel-style ‘Acorn OS.’

See Acorn OS P1 vs. P2 in the Video Below

According to Dickson, these so-called “P-series” prototype devices are essentially “the first step to any product.” As such, he added, they are unfinished, often built of the most inexpensive materials, such as plastic and unpolished bezels, and, perhaps because they are so raw, Dickson added, “they seldom if ever make it outside Apple’s walls.”

“These P unit prototypes are so early in the development process that they rely on a custom process to be turned off, and can only be powered down during a certain step of the boot process,” he wrote.

Legend has its that as far back as 2005 — a full two years before the iPhone was announced — Apple’s late co-founder, Steve Jobs, had personally been experimenting with a few of these “P-series” handsets — likely in an attempt to narrow down the options and settle on a user interface that would, through continued tweaking and refinement, ultimately become iOS.