The new 4G iPod nano leaves behind the shorter, wider shape of the third-generation (3G) model to embrace the taller, slimmer profile of the nanos of old - even slimmer, in fact, than those older models.

When it comes to physical appearances, the fourth-generation iPod nano saw the biggest changes when Apple overhauled its iPod lineup this week.

The new iPod nano leaves behind the shorter, wider shape of the third-generation (3G) model to embrace the taller, slimmer profile of the nanos of old - even slimmer, in fact, than those older models. But along with its new shape, the fourth-generation (4G) iPod nano also incorporates new hardware features and new software.

The two new 4G iPod nano models double the capacity of their predecessors, offering 8GB of flash memory for £109 and 16GB for just £40 more.

Apple has also gone back to the wraparound, anodised-aluminum design of the 2G nano, increased the number of available colours from six to nine - black, silver, pink, red, orange, yellow, green, blue, and purple - and made those colours much more vivid. Each model is available in all nine colours.

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