Home How to Jailbreak iOS 4.0 for iPhone 3G

How to Jailbreak iOS 4.0 for iPhone 3G

Apple has released its latest iPhone operating system, iOS 4.0, and just as quickly, the hacker community has managed to jailbreak it. For the uninitiated, “jailbreaking” refers to the ability to open up a device in order to install unapproved, third-party applications. Given both AT&T and Apple’s restrictions regarding the iPhone, this process is a must for many Apple device owners.

Jailbreaking allows for a plethora of new features, including turning the phone into a Wi-Fi hotspot, being able to fully customize the phone down to its icons and forcing Wi-Fi only apps to run over 3G. For those whose older devices don’t support all of iOS 4’s new features, jailbreaking offers some viable alternatives. 

Jailbreaking vs. Unlocking

Jailbreaking and unlocking the iPhone are two different hacks which allow you to take control of your mobile device in different ways. Jailbreaking is a type of hack that lets you install unapproved third-party applications on your iPhone or iPod Touch from searchable repositories provided by apps like Cydia and Icy. Unlocking, on the other hand, is a hack that lets you use your iPhone on another cellular network. Here in the U.S., that means you can use the iPhone on T-Mobile instead of AT&T. You have to first jailbreak your phone before you can unlock it, but you don’t have to unlock a phone in order to jailbreak it.

How to Jailbreak the 4.0 Software for the iPhone 3G and iPod Touch Second Generation

The “Redsn0w” jailbreak software has been updated to support iOS 4.0 on both Mac and Windows and works for iPhone 3G and the iPod Touch, second generation. This jailbreak is especially helpful for for iPhone 3G owners as the new OS won’t offer the much sought-after multitasking feature on their devices. A jailbreak application called multifl0w will, however, provide an alternative. Another jailbreak app called WinterBoard offers a way to customize the iPhone’s background even though that too is disabled for 3G owners running the latest OS 4.0 update.

This jailbreak guide assumes you’ve already downloaded and updated your phone or iPod Touch to the latest software, iOS 4.0, and have backed up your device.

If you are looking to unlock your phone in order to run it on a network belonging to another carrier, this is not the guide for you.

How to Jailbreak iOS 4 on Non-iPhone 4 Devices

  1. Download Redsn0w, version 0.9.5b5-3 (Links: Mac OSX (x86), Windows Updated file locations: Mac, Windows)
  2. Extract the files and run the Redsn0w executable. (Windows users should run it as Administrator)
  3. When prompted, point it to the original iOS 4 firmware file (in Windows, browse to C:UsersusernameAppDataRoamingApple ComputeriTunesiPod Software Updates and look for the .ipsw file; on Mac, the file will be here: ~/Library/iTunes/iPhone Software Updates/)
  4. On the following screen, make sure “Install Cydia” is selected. You can check or uncheck the other options as desired.
  5. If you phone isn’t already off, turn it off now. (Press and hold the power button at the top until the “Slide to turn off” message appears, then shut the phone down).
  6. Plug the phone into your computer via the USB cable, if you haven’t done so already.
  7. Here it gets a little tricky. The following screen instructs you on a combination of button presses that will force the phone into a special mode called “DFU” mode. You don’t need to know what that means, but you need to follow the instructions precisely. If you mess up, it’s OK. You’ll just get an error message and can then go back and try it again.
  8. After successfully entering DFU mode, the jailbreaking processing will begin. You’ll see file copying procedures taking place, but there’s nothing else you really need to do except for hitting the “Finish” button when the computer portion of the jailbreak ends. (The rest of the jailbreak happens on your phone).
  9. When your phone reboots, look for the new Cydia icon on your homescreen. From this jailbreak App Store, you can download all the applications that aren’t allowed into Apple’s curated and approved collection.

Keep in mind that if you have a jailbroken phone, you can’t get support from Apple for any issues you may have. However, jailbreaking isn’t permanent. You can revert your phone to its factory settings at any time via iTunes with no one the wiser.

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