If you care about jailbreaking on iOS 4.0, it is recommended that you stay on whatever firmware you are on know because the vast majority of jailbreak apps and tweaks do not work on the firmware. Let the developers sort out all the updates beforehand.

Also, if you care about unlocking your iPhone, do not update! It has been confirmed that the firmware is unlockable but the unlock doesn’t come out until later so do not update yet!

There is no jailbreak for the firmware that is about to be release at the momemt, that will change very shortly after release, but if you want to jailbreak some form on iOS 4.0, you can jailbreak one of the betas using Redsn0w 0.95 beta 5.

A new update has been issued for the iOS 4.0 jailbreak Redsn0w. The version number is now 0.95 beta 5 – 2 and updates include the ability to enable verbose mode and battery percentage.

How to use it:

1. Make sure you’ve already activated your iPhone3G or iPod Touch 2G with iTunes (redsn0w won’t hacktivate your iPhone3G until Apple’s full public release of 4.0)
2. Launch the beta redsn0w 0.9.5b5
3. Select your stock 4.0 ipsw (you’ve already used this to update your device to 4.0)
4. Select “Install Cydia” and click “Next”. Use DFU mode to install the jailbreak.
5. When your device comes back up, you’ll notice Cydia has a blank white icon (we told you many things were broken right now!) Allow Cydia to reorganize, then accept the update it offers. When Cydia restarts, you should see its real logo now.

Downloads:

Mac OSX x86
Windows
Here are mirrors if those downloads don’t work:

Download Redsn0w 0.9.5 Beta 5 for Windows.

Download Redsn0w 0.9.5 Beta 5 for Mac OS X.

This BETA release supports:

• iPhone 3G and iPod touch 2G only (for now)
• Mac OSX and Windows only (for now)
• the 4.0beta1/beta4/GM FW only (for now)

How to use it:

1. Make sure you’ve already activated your iPhone3G with iTunes and your developer UDID
2. Launch the beta redsn0w 0.9.5b5
3. Select your stock 4.0 ipsw (you’ve already used this to update your device to 4.0)
4. Select “Install Cydia” and click “Next”. Use DFU mode to install the jailbreak.
5. When your iPhone3G comes back up, you’ll notice Cydia has a blank white icon (we told you many things were broken right now!) Allow Cydia to reorganize, then accept the update it offers. When Cydia restarts, you should see its real logo now.

Downloads:

Mac OSX x86
Windows

Good news for all the developers out there who had to update to the iOS 4.0 GM version. The Redsn0w 0.9.5 beta 5 can jailbreak the firmware on the iPhone 3G which has been legitly activated.

For those with legit iPhone3G activation on 4.0GM seed, redsn0w from 2 wks ago can JB your device.

The Dev Team have also said to stay well clear of iOS 4.0 with Yell0wsn0w, Blacksn0w or Purplera1n.

For those who can legitimately activate to the iPhone3G 4.0GM seed, the “point to previous IPSW” redsn0w trick works and will jailbreak your 4.0GM. The “trick” is to point redsn0w at the 4.0beta4 IPSW instead of 4.0GM (do this after you’ve updated to 4.0GM and activated through the new iTunes 9.2 on your Mac). Since the carrier unlocks aren’t yet supported at 4.0, don’t do this if you use yellowsn0w/ultrasn0w/blacksn0w. Many JB apps are still pretty buggy in 4.0, so again this ismostly useful only for developers of those JB apps.

You can download it by clicking HERE.

How to use it:

1. Make sure you’ve already activated your iPhone3G with iTunes and your developer UDID
2. Launch the beta redsn0w 0.9.5b4
3. Select your stock iPhone OS 4.0 GM IPSW file.
4. Select “Install Cydia” and click “Next”. Use DFU mode to install the jailbreak.
5. When your iPhone3G comes back up, you’ll notice Cydia has a blank white icon (we told you many things were broken right now!) You’ll also notice Cydia has no sources. Go to the Sources panel and add this repo: http://apt.saurik.com/cydia-3.7 (be sure you have a carrier or wifi signal first!). When Cydia restarts, you should see its real logo now, and the standard sources should be ready to use.

The Dev Team have released the latest version of Redsn0w for all the developers out there who have to update to the latest OS 4.0 betas despite loosing their jailbreak. This latest version can jailbreak your iPhone/iPod Touch which is on OS 4.0 beta 4. The is intended only for developers.

Redsn0w version 0.95 is meant for developers as they are the only ones who are *supposed* to have the iPhone OS 4.0. Naturally, someone somewhere did leak it onto the internet meaning quite a few peolpe updated without realizing you need your UDID on a dev’s account. So, this jailbreak is only intended for devs. DO NOT INSTALL OS 4.0 IF YOU ARE NOT A DEV!

Also, do not updated your iPhone if you are planning on unlocking your iPhone as OS 4.0 contains a baseband update.

As OS 4.0 can only be installed by dev and you can only be a dev if you have a Mac, Redsn0w 0.95 was only released for Mac users.

Click to download: HERE

The program is really easy to use. You will need the OS 4.0 firmare files for this to work:

What is it?

What devices, platforms, and FW versions are supported?

How do I use it?

Help! I should have listened and just left this for JB app devs!

Apple have released a new version of iTunes with changes include support for iPad syncing and security improvements. Generally, it is safe for jailbreakers as all of Dev Team’s tools, PwnageTool and Redsn0w, still work on it however, GeoHot’s Blackra1n tool no longer works so if you are planning on using that, do not update!

EDIT: There is now a fix for the Blackra1n problem.

This is after the problem caused when Apple both released a new iPhone/iPod Touch firmware OS 3.1.3 (which contained only bugfixes) and the fact that they suddenly stopped signing the OS 3.1.2 firmware. This means users who needed to restore, couldn’t restore to OS 3.1.2 any more but only to OS 3.1.3.

There already are some jailbreaks for OS 3.1.3, Redsn0w and Sn0wybreeze, but as Redsn0w doesn’t work for the iPhone 3GS and iPod Touch 3rd gen, some users will still need PwnageTool. Sn0wybreeze is not getting very good reviews at the moment and it probably would be wise to wait for PwnageTool rather than Snowybreeze.

But as MuscleNerd says, if you are not having any trouble with OS 3.1.2, do not update. There is no point.

Sn0wbreeze is essentially a Windows port of the Dev Team’s PwnageTool. It allows you to create custom IPSW firmwares (allowing you to maintain your current baseband when updating).

The Sn0wybreeze jailbreak ONLY jailbreaks iPhone (iPhone 2G, 3G and 3GS (with old bootrom) so if you have an iPod Touch, you will still need to use Redsn0w.

DO NOT use custom boot logos with the iPhone 3GS as you will get an error when installing it.

There is no current jailbreak (Sn0wybreeze or Redsn0w) for the iPod Touch 3rd generation or iPhone 3GS with the new bootrom.

Click to download: Sn0wbreeze OS 3.1.3 (588)

Therefore, this guide only works on iPod Touch 1st and 2nd gen (without MC in serial code), the iPhone 2G, 3G and 3GS (without MC in serial code).

The guide is relatively simple. For this, you need two things:

• Firmware OS 3.1.2 for your device: DOWNLOAD
• Redsn0w: Redsn0w 0.9.2 (MAC) (4124) or Redsn0w 0.9.2 (WIN) (35331)

What to do:

1. Unzip the Redsn0w program and place the .ipsw file in the Redsn0w application folder like so:
   
2. Open up the Redsn0w program and direct the program to the IPSW file for your device. And the following menu will pop up. Since this guide only works with non-MC serial coded devices, you click NO (if that is the right answer. If it’s yes, this guide is not for you).
   
   Click next.
3. You will be presented with the below menu.
   
   This guide assumes you have already got a jailbroken device and therefore you should deselect ‘Install Cydia’ and select ‘Already pwned’. You can then select verbose mode or the custom boot logos and you wish.
   Note: Verbose mode changes you booting so that it shows what is happening within the device whilist it starts up. It is a punch of code running down the scree and looks pretty awesome
   
4. Click next and Redsn0w will ask you to put your device into Recovery mode (NOT DFU MODE). To do this, simply hold down both buttons until the recovery picture comes up (this can take a while, even 3 minutes). It will look like below:
   
5. Redsn0w will now automatically do its stuff. Leave the device along until it reboots again.

You will now have a custom boot logo and recovery logo.

Boot logos:

Here are some boot logos for you to select in the program:

As I said, you can ONLY do this if you click make my life easier on Cydia before yesterday which allows Cydia to backup your SHSH file. You should see this when you launch Cydia.

To downgrade your firmware you will need to change a line in the hosts for Cydia redirecting iTunes to download the signature file from Saurik’s server rather than Apple’s.

Guides are courtosy of ihackintosh.com:

How to Edit and Save Hosts file in Windows

• Open Notepad with Administrative privileges by clicking Start, All Programs,Accessories, and thenright-click Notepad and select to open as Administrator.

• Now that Notepad is open with Administrative privileges browse to (C:WindowsSystem32driversetc) in Notepad and open the hosts file, and add the following entry to the bottom of the file.
  

  74.208.10.249 gs.apple.com

Now you navigate to files menu and save the hosts file. By doing this you changed the communication server, and then we will ensure that iTunes checks the firmware on the server rather than opens Saurik toApple! Because your ECID is on that server, the verification will fail and restore the previous version will be done without too many problems!

_____________________________________________________________________________________

How to Edit and Save Hosts file in Mac OS X

• Navigate to /etc and look for hosts file, right click on hosts file and open with Text Edit, and add the following entry to the bottom of the file.

74.208.10.249   gs.apple.com

• Now save the file and click on Save As.
• Because Text Editor can’t save your system files, here comes the tricky part, in save as windows use the following settings. Or take a close look at the following image.

1. In Where locate to Desktop
2. Uncheck the “ If no extension is provide, use .txt “ and then press the save button.

• A host file will be appear on your Desktop, just drag and drop to /etc and follow the onscreen instructions.
• Press the Replace and enter your Password

By doing this you changed the communication server, and then we will ensure that iTunes checks the firmware on the server rather than opens Saurik to Apple! Because your ECID is on that server, the verification will fail and restore the previous version will be done without too many problems!

You will now be able to downgrade your device to OS 3.1.2 from OS 3.1.3.

Simply place your device into DFU mode and click SHIFT+RESTORE, select your firmware file and you will be downgraded.

If you receive 1011, 1013, 1015 errors simply ignore them as your firmare is still properly installed. Just go ahead to Blackra1n or Redsn0w and jailbreak your device.

If you receive 1601, 1602, 1600 errors, you will need to put your device into DFU mode once again and try install the firmware once again.

You can download the program from below: (Downloads have been corrected)

• Redsn0w 0.9.4 (MAC)
• Redsn0w 0.9.4 (WIN)

For guides, the process is exactly the same as for OS 3.1.2 with Redsn0w so therefore the below guides are still relevent. Simply direct the OS 3.1.2 firmware to the program (as said in the guide) EVEN THOUGH you have OS 3.1.3 on the device.

How to Jailbreak your iPhone 3GS on OS 3.1.2 with Redsn0w 0.9.2 (MAC)

How to Jailbreak your iPhone 3GS on OS 3.1.2 with Redsn0w 0.9.2 (WIN)

If you want more customizable jailbreak, you can use PwnageTool (for Macs) or Sn0wybreeze (for Windows) to make custom IPSW for jailbreaking your devices.

Redsn0w is a jailbreaking tool created by the Dev Team which allows you to jailbreak your device as well as change the boot logo and enable verbose mode.

This guide is for Mac. For Windows go here.

Full credit for this guide goes to iClarified.com.

Step One
Create a folder on your desktop called Pwnage

Download RedSn0w from here and place it in the Pwnage folder. Likewise, download the latest 3.1.2 firmware from below and place it in the same folder.

3.1.2 (3GS): iPhone2,1_3.1.2_7D11_Restore.ipsw

Double click the redsn0w zip file to extract the redsn0w folder to the Pwnage folder.

Step Two
Connect your iPhone to the computer and launch iTunes.

Select your iPhone from the list of devices on the left. Now hold down Option and click the Restore button. Restore is preferred as it won’t create any wasted space on your iPhone.

Navigate to the Pwnage folder on your desktop and select the firmware ipsw. Click the Open button to continue.

*Note: If you are already on the 3.1.2 firmware and have not jailbroken then you may skip this step.

Step Three
Once iTunes has finished updating your iPhone to the desired firmware open the Pwnage folder on your desktop and launch the redsn0w application from the redsn0w folder we extracted earlier.

Step Four
Once RedSn0w opens click the Browse button

Step Five
Select the firmware ipsw we placed in the Pwnage folder on our desktop then click Open

Step Six
RedSn0w will ask you if this is a newer (fixed) model iPhone. Newer models of the iPhone 3GS have a fixed bootrom which requires you to connect your device to the computer each time you wish to reboot.

To find your serial number you can follow these instructions. The week number is usually the 4th and 5th digit of the serial number. For example, a serial number beginning with 88926 would be week 26 of 2009. 3GS units made week 45 or later will usually have a fixed bootroom. Before week 40 they usually have the older bootroom. Between weeks 40 and 45 the results vary.

If you believe your device has a fixed bootrom then press the Yes button. Otherwise press the No button.

If you accidentally select the wrong option you may have to do a full restore so please make this choice carefully.

Step Seven
Once the firmware has been verified click the Next button to continue.

Step Eight
RedSn0w will now prepare the jailbreak data

Step Nine
From this window you can select the jailbreak options you would like. If you have already pwned your device check the Already pwned option.

Verbose boot displays detailed information on boot of your device and is generally only needed by developers and advanced users.

Make sure Cydia is selected. For this tutorial we will also select Custom boot logo and Custom recovery logo.

When you click to select each custom logo option a dialog window will appear asking you to select the image. Locate the image you would like to use then press the Open button.

*Remember the rules for boot logos are: RGB or Grayscale format with Alpha channel and dimension below 320×480.

Click the Next button to continue

Step Ten
RedSn0w will now instruct you on how to put your iPhone into recovery mode. Disconnect you iPhone 3GS from the computer then power it off. Then hold down the Home button while reconnecting the device to the computer. Don’t let go of the button until RedSn0w detects the iPhone and begins installation.

Step Eleven
Your iPhone will now reboot

Step Twelve
RedSn0w will then begin uploading the new RAM Disk and kernel.

Step Thirteen
Once this is complete you will be notified that RedSn0w is done. Click the Finish button. When your iPhone finishes rebooting (5 minutes or so) it will be jailbroken with Cydia on the SpringBoard.

This guide is for Windows. For Mac go here.

Full credit for this guide goes to iClarified.com.

Step One
Create a folder on your desktop called Pwnage

Download RedSn0w from here and place it in the Pwnage folder. Likewise, download the latest 3.1.2 firmware from below and place it in the same folder.

3.1.2 (3GS): iPhone2,1_3.1.2_7D11_Restore.ipsw

Extract the RedSn0w executable from the zip file to the Pwnage folder.

Step Two
Connect your iPhone to the computer and launch iTunes.

Select your iPhone from the list of devices on the left. Now hold down shift and click the Restore button. Restore is preferred as it won’t create any wasted space on your iPhone.

Navigate to the Pwnage folder on your desktop and select the firmware ipsw. Click the Open button to continue.

Step Three
Once iTunes has finished updating your iPhone to the desired firmware you may launch redsnw0w.exe from the Pwnage folder on your desktop.

Step Four
Once RedSn0w opens click the Browse button

Step Five
Select the firmware ipsw we placed in the Pwnage folder on our desktop then click Open

Step Six
RedSn0w will ask you if this is a newer (fixed) model iPhone. Newer models of the iPhone 3GS have a fixed bootrom which requires you to connect your device to the computer each time you wish to reboot.

To find your serial number you can follow these instructions. The week number is usually the 4th and 5th digit of the serial number. For example, a serial number beginning with 88926 would be week 26 of 2009. 3GS units made week 45 or later will usually have a fixed bootroom. Before week 40 they usually have the older bootroom. Between weeks 40 and 45 the results vary.

If you believe your device has a fixed bootrom then press the Yes button. Otherwise press the No button.

If you accidentally select the wrong option you may have to do a full restore so please make this choice carefully.

Once the firmware has been verified click the Next button to continue.

Step Seven
Make sure Cydia is selected and click the Next button.
From this window you can select the jailbreak options you would like. If you have already pwned your device check the Already pwned option.

Verbose boot displays detailed information on boot of your device and is generally only needed by developers and advanced users.

Make sure Cydia is selected. For this tutorial we will also select Custom boot logo and Custom recovery logo.

When you click to select each custom logo option a dialog window will appear asking you to select the image. Locate the image you would like to use then press the Open button.

*Remember the rules for boot logos are: RGB or Grayscale format with Alpha channel and dimension below 320×480.

Click the Next button to continue

Step Eight
RedSn0w will now instruct you on how to put your iPhone into recovery mode. Disconnect you iPhone 3GS from the computer then power it off. Then hold down the Home button while reconnecting the device to the computer. Don’t let go of the button until RedSn0w detects the iPhone and begins installation.

Step Nine
Your iPhone will now reboot

Step Ten
RedSn0w will then begin uploading the new RAM Disk and kernel.

Step Eleven
Once this is complete you will be notified that RedSn0w is done. Click the Finish button. When your iPhone finishes rebooting (5 minutes or so) it will be jailbroken with Cydia on the SpringBoard.

This release supports:
All iPhones and iPod touches (still a tethered-only JB for late-model devices though)
Apple firmware 3.0 and 3.1.2
Windows and Mac OSX (x86)

It will also soon run on the PPC OSX, and Linux platforms.

If you need a carrier unlock, redsn0w will handle iPhone 2G by itself (by installing our BootNeuter utility). For the 3G and 3GS, use Cydia after you’re jailbroken to install ultrasn0w (baseband 04.26, preferred) or blacksn0w (baseband 05.11).

How does it differ from Blackra1n?

Unlike the Blackra1n, RedSnow installs Cydia, and the IPCC tethering hack without needing separate downloads.

How long should it take?

You should see a picture of a drive (“Downloading Jailbreak Data”) within 30 seconds of launching the jailbreak (after you’ve made your custom selections). It should then reboot and you should see a running pwnapple while the process is underway. It should finish within a minute or two after that, and will reboot on its own.
Is it safe?

The Windows version has been tested by small groups of volunteers on IRC and our blog since mid-January. That being said, if things go wrong you may have to do a system restore…so make sure your data and pictures are synced before trying it.

Download Links:

• Redsn0w 0.9.2 (WIN) (35331)
• Redsn0w 0.9.2 (MAC) (4124)

How to Jailbreak your iPhone 3GS on OS 3.1.2 with Redsn0w 0.9.2 (WIN)

How to Jailbreak your iPhone 3GS on OS 3.1.2 with Redsn0w 0.9.2 (MAC)

Credits : iPhone Dev-Team, for making such a useful program for everyone using the iPhones and iTouches