redsn0w is a multi-platform jailbreak and unlock tool created by the iPhone Dev Team. redsn0w is very easy to use, and it supports all of the current iPhone and iPod Touch devices running on firmware 3.0.
REDSN0W PROVIDES SIMILAR FUNCTIONALITY TO QUICKPWN.
If you want to build custom firmware files with more flexibility it is suggested that you use Ã¢â‚¬ËœPwnageToolÃ¢â‚¬â„¢ on Mac OS X.
1. GOLDEN RULE: If you are using a 3G iPhone with yellowsn0w and rely on yellowsn0w to obtain cellular service, then you should NOT use redsn0w right now. Ultrasn0w (the 3G carrier unlock) is not included with this release and therefore your baseband will be locked and unable to use an operator other than the official one it was bought for. UltraSn0w will be released via APT (cydia and icy) soon. If you have an original iPhone (1st generation) then 3.0 carrier unlock works with this redsn0w release.
2. Yellowsn0w in its current form will NOT work with the baseband version that is present in the 3.0 update, you will need Ultrasn0w, which will be released sometime soon, Ultrasn0w will work with all iPhone 3G models (but not 3GS), even ones that were previously unlockable, Ultrasn0w (when available) will be released via APT (this means you will be able to get it via Cydia or Icy).
3. Please read all parts of this post before downloading and using these tools.
4. Read items 1, 2 and 3 again and again.
5. At the bottom of the download link are the bittorrent files for the latest version of redsn0w.
6. This app is suitable for the recent 3.0 release
7. redsn0w will NOT work for the iPhone 3GS.
8. redsn0w WILL work for Original iPhone (1st Generation), Original iPod touch, iPod touch 2G and the iPhone 3G (not the iPhone 3GS).
To use redsn0w simply upgrade the device in iTunes to firmware version 3.0 and run redsn0w to activate and jailbreak the device (and if you are using an original iPhone 2G, it will unlock it too!)
Works on Windows Linux and Mac OS X.