Actually we can find many Youtube videos for iPod Nano jailbreak. Normally free best Jailbreak tools are Evasi0n, Redsn0w, Sn0wbreeze, P0sixspwn, Absinthe.
If your device is running with iOS 7 use - Evasi0n
If your device is running with iOS 6 use - Evasi0n
If your device is running with iOS 5 use - Redsn0w , Absinthe
Also we can find solution with Sn0wbreeze,
My Recommendation
If you have iPhone, iPod, iPad or Apple TV devices, you can jailbreak using above mentioned tools. But i never jailbeak iPod Nano devices. So my recommendation is do not go to jailbreak iPod Nano device. You need to find proper way to jailbreak your device. Otherwise your device warranty may be loss or device may be brickl
Hold down the MENU and Center Button for approximately 6 seconds.
Before the Apple logo appears, hold down the Rewind Button and the Center Button for approximately 6 seconds.
You will see yellow and white text.
The click wheel will not function, so use the Fast Forward and Rewind buttons to go up and down. The Center Button and MENU button still function as always.
To get back into normal mode, hold down the MENU and Center Button for approximately 6 seconds again without pressing the Rewind Button and the Center Button.
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