Its three months since iPhone/iPod users are using 3.1.2. Today Apple announced the latest update for iPhone/iPod the 3.1.3 which includes few minor bug fixes, although OS 4.0 was expected this 27th of January, but only iPad was unveiled on 27th of January. redsn0w is an jailbreaking tool for iPhones and iPod touches, you can jailbreak your iPhone 2G, 3G, iPod touch 1G, 2G(non-MC) with redsn0w. Use f0recast before you continue to check whether your jailbreak will be tethered or untethered and whether you iPhone is unlockable or not. To check your device is non-MC go to Settings=>General=>About If it has MC in the start of the serial number then it is MC otherwise not. iPhone 3GS users click here to jailbreak your iPhone.

You also can use this tutorial to unlock your iPhone 2G, 3G, 3GS(non-MC) using sn0wbreeze.

Pre-requisites are:

  - redsnow (Windows / Mac)
  - iTunes
  - 3.1.3 and 3.1.2 IPSW file for your device (google it to get it)

To update your iPhone OS

1- Connect your iDevice(iPhone/iPod) with PC.

2- Launch iTunes, if you already have downloaded the IPSW file for your device Shift click on Restore and select the IPSW file.

Else click on update and iTunes will check for latest updates.

Click on Update to download and install the 3.1.3 OS on your iPhone. (In case of iPod you have to download the IPSW file first, as update for iPods are not free).

4- After your iDevice has been updated, Launch redsn0w. This part is tricky, you have to point to 3.1.2 IPSW file because 3.1.3 IPSW file still is not validated by redsn0w, so click on Browse and select the 3.1.2 IPSW file for your device.

5- redsn0w will validate the file, now click Next.

6- Select Install Cydia, and Already pwned (if you dont want to use the supported carriers) and click Next.

7- At that point make sure that your iPhone is both off and connected to PC, now connect your iPhone with recovery mode, by pressing the Power and Home button simultaneously for around 5 seconds.

8- Here you will be presented with a screen which requires you to press the power button for a while, then power and home button simultaneously, and after a while release the power button while still holding the home button until the installation starts.

9- Now its redsn0w's turn to do the rest. After its done, your device will restart, and voila, your iDevice has been jailbroken successfully.

Note for iPhone 2G users: You can unlock your iPhone using BootNeuter app from Cydia, launch cydia and search for BootNeuter, install and restart iPhone, alternatively you can follow this tutorial to jailbreak and unlock your iPhone 2G

iPhone 3G and 3GS users: Click here to unlock your iPhone using blacksn0w or ultrasn0w

Enjoy.