Apple historians may know that before Cupertino settled on going with iOS as the iPhone s software, it considered adapting the iPod s interface and OS to power the now-iconic smartphone, including the MP3 player s click-wheel.

The original prototypes of that software have never been seen before, but frequent leaker Sonny Dickson has managed to get his hands on a selection of screenshots and even video, revealing what was once known as AcornOS.

Anyone s who s familiar with the iPod Classic or any of the model came before will recognize the UI seen in the images.

The top half of the screen features a list of menus that can be scrolled through, just like on the iPod, while the bottom half is made up of a software-based click-wheel, allowing users to make circular gestures on the display to navigate up and down.

Right through the middle are the familiar Menu, repeat/advance, and play/pause buttons, also straight from the iPod.

As for the menu options, along with Music and Photos are a number of phone-related sections, including Dial, SMS, and Contacts.

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