iPods may get two-faced, according to Apple's latest patent filing.

The patent describes a device – perhaps an iPod – which offers touch-sensitive controls on both sides that are designed to control the cursor and work the system.

The US Patent Office filing (number 20070103454) was filed on 5 January and published on 10 May.

The device - which has already been dubbed the 'iPhone nano in some quarters – suggests the technology could be used in a handheld computer system, mobile phone or digital music player.

The patent filing specifically states that the video iPod hosts a display that is "often too small to make effective use of finger-based touch input'. It also notes that touch-sensitive screens can easily be 'smudged' in use, to the detriment of the video playback experience.

In use, a user would be able to see the controls on the screen on the front of the device, and manipulate those controls using touch-sensitive controls situated on the back of the device.

Control menus would change in the same manner as they wil do on the iPhone – users will be navigating different menus which pop-up on the main screen whenever they are trying to manipulate a different function: navigating video collections or choosing music, for example.

The filing explains: "An electronic device uses separate surfaces for input and output. One of the surfaces (eg., the bottom) includes a force-sensitive touch-surface through which a user provides input (eg., cursor manipulation and control element selection). On a second surface (eg., the top), a display element is used to present information appropriate to the device's function (eg., video information), one or more control elements and a cursor.

"The cursor is controlled through manipulation of the back-side touch-surface. The cursor identifies where on the back-side touch-surface the user's finger has made contact. When the cursor is positioned over the desired control element, the user selects or activates the function associated with the control element by applying pressure to the force-sensitive touch-surface with their finger. Accordingly, the electronic device may be operated with a single hand, wherein cursor movement and control element selection may be accomplished without lifting one's finger."