Jailbreaking an iPhone/iPod Touch or unlocking an iPhone removes restrictions on device applied by Apple and makes you able to enjoy advanced apps/features. 
Jailbreaking and unlocking can be done easily with free tools available for everyone(check out our guide for Jailbreaking and unlocking iPhone). However you have to be careful with things like boot room and baseband compatibility etc before trying to unlock or jailbreak. F0recast helps you to know the basic information (specs) required to jailbreak or unlock your iPhone or iPod Touch. It helps you to know if your device is unlockable or tethered with just a simple USB connect.
f0recast is developed by ih8sn0w team and it’s available for Windows only. Download f0recast now.
Important
Now you can do untethered Jailbreak of your iPhone 3G/3Gs running latest firmware 3.1.3 with "Spirit".
Step by Step iPhone 2G/3G/3Gs Firmware 3.1.3 Jailbreak Guide Using Spirit
[ithinkdiff via BlogsDNA] – screenshot by ih8snow
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