How to jailbreak iOS 4

The dev team recently released a new PwnageTool that will allow you to jailbreak iOS4 on your iPhone or iPod touch. Since we covered that, the dev team has upgraded the PwnageTool to 4.0.1.  This is our walkthrough of  how to jailbreak devices running iOS4. As always here's our disclaimer;

If you are in any way, shape, or form hesitant to jailbreak your device, don't!  We take no responsibility for whatever damage you may do to your device during or after the process.  Jailbreaking should typically be reserved for semi-advanced to advanced users.  Preliminary jailbreaks can sometimes cause more problems.  This jailbreak is NOT as simple as a button click like blackra1n or Spirit.  If that's what you'd prefer, wait for that... pass on this one."

If you're alright with all of that, hit the jump to see if your device can currently be jailbroken/unlocked and how to do it.

Sorry I don't have a video for you guys this time, I had my 3GS swapped due to it bricking hardcore, and I have the newer baseband, but for now, here's a nice walkthrough. I'll update with a video when the dev team has a solution for newer basebands on 4.0.

iPhone Family (Mac Only)

iPhone 4

  • Not currently supported, so please don't attempt as you may damage your phone. As with all new hardware, you'll have to wait a bit for an update that supports iPhone 4.

iPhone 3GS

  • New bootrom: No
  • Old bootrom and haven't ever jailbroken with Spirit but HAVE been jailbroken before: yes, you can jailbreak
  • An easy way to tell if you have an older or newer bootrom is to check your serial, if the 4th and 5th digits are 40 or less, you've got an older bootrom. (ie - if my serial was 8B4387323 I'd be okay as my phone's 4th and 5th digits are 38)

iPhone 3G

  • Easiest way, just use redsn0w regardless of your situation, it should work, or follow the directions below

iPod Family (Mac and Windows)

iPod Touch G2

  • The second generation iPod touch is currently the ONLY iPod touch that is compatible with PwnageTool 4.0.1 at this time.  If you have a first or third generation, you'll have to wait a bit longer. Either follow the directions below for second generation iPods or use redsn0w if you have a non-MC model of the 2nd gen iPod touch, basically older bootrom)


Alright, now that we've determined whether or not you're capable of jailbreaking, I'm assuming you'd only be reading this if you're "certain" you can.  Here's what you need to do:

  1. Back up your iPhone/iPod in iTunes
  2. Download PwnageTool here from the official source or one of the many mirrors
  3. Make sure your device is connected and open PwnageTool
  4. PwnageTool will ask you to select your device (I always select expert mode by the way, it will give you more choices when building your custom firmware - for iPhone 3G users who would like to activate the multi-tasking functionality, etc, you'll need to select expert mode and further down in the process, you'll be able to select an option that will enable features like multitasking, it may lag though, so consider yourself warned.)
  5. Then select Next and PwnageTool will browse for firmwares on your computer. If for some reason your computer does not find them, you can get firmwares from here. (Remember to make SURE you are downloading the correct firmware for your device.  iPhone 1st gen = 1,1 - iPhone 3G = 1,2 - iPhone 3GS = 2,1 - iPhone 4 = 3,1
  6. After PwnageTool finds your correct firmware or you have browsed to the firmware you have downloaded, click next.
  7. (Simple Mode, skip to step 11) If you selected expert most, you will now get a screen asking you to customize your build, select general at the very least, and typically Cydia packages, if you'd like the pineapple logo instead of the Apple logo, select Custom Logos then click next.
  8. Next you will get a screen asking you to partition your space for jailbreak stuff (you don't have to). It'll also ask you if you'd like to activate, uncheck this if you're on AT&T and not unlocking.
  9. The next screen will allow you to select custom packages you'd like pre-installed. Select what you want and click next again.
  10. Select your custom boot logos or browse for your own and click Next.
  11. Select Build on this screen, it'll prompt you for a location to save your custom IPSW, I normally save this to my desktop. (Oh, don't stray too far away from your computer, you'll probably be asked for an admin password at some point during the build process).
  12. Once your bundle is done you'll need to open iTunes and put your phone into DFU mode. Simply turn your phone completely off, open iTunes, and hold down your home button until iTunes recognizes there is an iPhone/iPod in recovery mode.
  13. Next hold down alt+option on your keyboard and click restore, navigate to your custom firmware you just built and restore from that. If all went well, your iPhone/iPod should reboot jailbroken!

Unlocking iPhone 3G and 3GS

As ultrasn0w now supports ALL versions of iPhone basebands, if your jailbreak was successful, you just need to install ultrasn0w via Cydia and you'll be unlocked!

If you have any questions or concerns with this process, feel free to leave them in the comments, forums, contact me on Twitter @iMuggle, or shoot me a quick e-mail at! Happy jailbreaking!

Allyson Kazmucha

iMore senior editor from 2011 to 2015.