In the early days of the iPhone’s development, Apple investigated two approaches for its future smartphone: building on top of the successful but functionally limited iPod operating system, or trying to scale down the powerful but complex Mac OS X platform. Steve Jobs chose the latter, but we now have a glimpse at a very early iteration of the former.

Noted Apple leaker Sonny Dickson has posted screenshots and video of what he claims is an early iPhone prototype concept based on the iPod. Dubbed “Acorn OS,” the system’s user interface is based around the familiar iPod menu structure at the top with a virtual click wheel and navigation buttons on the bottom of the screen.

With a copyright date of 2006, the interface is nearly identical to that found on the iPods of the time, with the primary difference being the existence of phone-related features such as “Dial” and “SMS.” Of note, however, the device doesn’t appear to include a Web browser, which was one of the original iPhone’s most important features.

There’s no way to prove the authenticity of the prototype operating system, but its design does closely resemble the drawings featured in one of Apple’s 2006 patent applications. While this design, if authentic, is an interesting part of Apple’s history, it’s safe to say that we can all be glad that Apple’s OS X-focused approach won out in the end.