While Apple and Palm talk up the legibility of screens on their diminutive devices, the nano and z22 have relatively low resolution when compared with more expensive models.

ENGADGET: Switched On: The Game Boy Micro pulls off the screen play

"We are excited by this new invention on transparent solar cells, which applied our recent advances in transparent conducting windows (also published in ACS Nano) to fabricate these devices, " said Paul S.Weiss, CNSI director and Fred Kavli Chair in NanoSystems Sciences.

ENGADGET: UCLA creates transparent solar cell, dreams of current generating windows

As an interactive window for iOS devices, a revamped nano could make the device even more palatable to those who purchased iOS products such as the iPad.

ENGADGET: Switched On: Next for the nano

Apple is likely to build iCloud service into all iOS devices, possibly including even entry-level products like the iPod Nano and Shuffle.

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