Apple has just released their new firmware update for iPhones, iOS 4.0. It comes with a lot of nice improvements to the OS. You can read about all of the changes here: http://www.engadget.com/2010/04/08/iphone-os-4-0-unveiled-shipping-this-summer/
However, the biggest bummer for owners of the iPhone 3G, like yours truly, is that the best feature of the new update, multitasking, isn’t usable on the iPhone 3G version of the iOS update! Apple will make a lot of noise about how the 3G isn’t powerful enough to handle multitasking, yadda yadda yadda, but I can tell you it’s more than capable of handling multitasking.
Ever since I’ve had my phone I’ve jailbroken it and installed an app called Backgrounder, which allows apps to run full time in the background. It works just fine. And this is background apps running as if they are open, this isn’t even the battery conscious, stripped down of multitasking that iOS 4.0 has. So you could imagine my surprise when I found out the new multitasking wasn’t going to be available for iPhone 3G owners.
But, good news! You can jailbreak your phone to enable the new multitasking to work on the iPhone 3G! It’s funny, the only reason why I jailbroke my phone in the past was to enable multitasking (and tethering, but that’s another post), and now that we have Apple sanctioned multitasking, I have to jailbreak it again to enable it on my phone.
This guide is meant for people who haven’t jailbroken their phone before, who have an iPhone 3G, and don’t want to shell out another $200 + 2 year contract to get these features which work just fine on their phones. I decided that a plain English guide was in order, considering that most of the guides out there assume that their readers have a good grasp on the whole dev scene. Most don’t, and this guide is for those people.
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Prep:
1. Download the official firmware update for your phone. Save it somewhere you can remember. I usually save it to the desktop in a new folder named “Jailbreak” for easy access. This file is around 300MB+ so it’ll take some time to download.
iPhone 3G users can get that here: http://appldnld.apple.com.edgesuite.net/content.info.apple.com/iPhone4/061-7436.20100621.58Yt4/iPhone1,2_4.0_8A293_Restore.ipsw
2. Download the jailbreak program, redsn0w and save it to the same folder that you saved the official firmware. Again, for easy access, not funtional requirement.
Download the Windows version here: http://sites.google.com/a/iphone-dev.com/files/home/redsn0w_win_0.9.5b5-4.zip
Download the Mac version here: http://sites.google.com/a/iphone-dev.com/files/home/redsn0w_mac_0.9.5b5-4.zip
*Note:* Mac users, you have to be on an Intel Mac. Most of you are, but just in case there are some PPC laggards out there.
3. redsn0w is an archived file, so unzip it within the same directory.
4. With all of the prep done, we can move on to updating your phone and jailbreaking it.
Backing Up & Updating:
1. Now this may seem counter intuitive, but you have to update your phone to the official Apple release of the firmware before you can jailbreak it. Trust me, it’s true.
2. Load up iTunes.
3. Wait for iTunes to load.
4. It’s finally up? Ok, now unlock your phone if there is a passcode then connect it to your computer. Your computer will take a bit to recognize the phone, but when it does it’ll show up in iTunes as normal.
5. Before we do any kind of updating or jailbreaking, you’ll want to back up your phone. Right click on your phone in the left panel and select the Backup option. Depending on your last back up, this might take a while. Just wait it out.
6. Once your backup is complete, we can move on to updating your phone to 4.0! But wait, don’t click the “Update” button. For a lot of iPhone 3G users, clicking the update button results in errors (Error 3002 to be exact). What we have to do is actually click the “Restore” button.
Counter intuitive, but again, trust me. I did it and it’s fine. What will actually happen is that in the process of restoring your phone, iTunes will download the 4.0 software and update your phone before restoring it. And since we just backed up your phone, you’ll restore from this latest backup! See, there is a reason for everything.
7. iTunes will download the update and apply it to your phone. This will take a while. Again.
8. After iTunes finishes updating your phone, it will ask you if you want to restore fresh or restore from a backup. Select the option to restore from your backup. This will also take a while.
9. Hey, it’s finished! Once the restore finishes, your phone will be updated to iOS 4.0 and all of your data will be there, right as rain. You can unplug your phone from the computer and mess with it a bit. Go ahead, I don’t mind.
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10. Back? Okay, did you notice how you don’t have multitasking or, hell, even the home wallpaper? Lame right? I know! Lets get to jailbreaking your phone so make things right with the world again!
Jailbreaking:
1. Remember where you saved redsn0w and the firmware? Kind of? Good thing we saved it to an easy to remember spot, right? Right. Go to the folder and run the redsn0w application.
2. The application will start and you’ll see this screen. Redsn0w jailbreaks phones by modifying the official firmware and then applying the new modified firmware to your phone. So the first thing you need to do is click Browse and select the firmware you downloaded.

3. Once you select the firmware, redsn0w will check out the file to make sure things are good to go. Once it does, you can click next to continue. If it finds any errors, there might be something wrong with your firmware download; go download it again to see if it fixes it.
4. The next screen allows you to select several options as part of the jailbreak. What we’re interested in here is the options of “Enable Multitasking”, “Enable homescreen wallpaper” and “Enable battery percentage”. Don’t bother with any of the other options for now; once you’re more adept, you can mess with them, but for now, just click Next.

5. This is the pre-game screen. After this, you’re in the game! So at this point, make sure iTunes is closed if it already isn’t. After it’s closed, you’ll notice that the screen asks you to turn off your phone and plug it into the computer. Don’t bother. Just plug in your phone to the computer. Once it recognizes it, THEN hold down the power button and turn your phone off.

6. OK, with your phone off, the next step requires some dexterity and interaction on your part. After you click next (don’t click it yet!), you’re going to do the following:
(This is just a practice run, don’t do these steps yet. Just read them over.)
- Hold down the power button for 5 seconds
- Then, while STILL holding down the power button, hold down the home button for 10 seconds.
- Then, while STILL holdind down the HOME button this time, let GO of the power button. Hold down the home button for 30 seconds.
- At some point (usually around 15 seconds left), redsn0w will show a success screen. You can now let go of the home button.
If it doesn’t work, don’t worry; you can do it again! Nothing bad will happen.
9. Okay, you got it? Okay, click next and start the jailbreaking dance:
(This is not a drill! Follow and do these steps!)
- Hold down the power button for 5 seconds
- Then, while STILL holding down the power button, hold down the home button for 10 seconds.
- Then, while STILL holdind down the HOME button this time, let GO of the power button. Hold down the home button for 30 seconds.
- At some point (usually around 15 seconds left), redsn0w will show a success screen. You can now let go of the home button.

10. After this point, your phone screen will show a hard disk with some copy along the lines of “Jailbreaking Device”. Your job is done! Just sit back and wait for the phone to finish updating. This usually takes 10 minutes.
11. If anything goes wrong, don’t fret. You can always go back to iTunes and restore your phone. Trust me, I’ve done it plenty of times.
12. After the phone is finished getting jailbroken, you’re set! Your iPhone 3G is now jailbroken and you have access to all of the new features and you didn’t even need to buy a new phone. But shh, don’t tell Apple that.
Advanced Features:
1. For those of you noticed, there is now an icon named “Cydia” on your phone, and it’s a white blob. This is the app store of the jailbreaking community. In here you can find all kinds of cool stuff like tethering programs, lock screen dashboards, themes, and other non-Apple sanctioned apps. If you want to partake, you need to setup Cydia. It’s easy, really.
2. To setup Cydia, just tap the white blob of an icon for Cydia. It will load.
3. Allow it to reorganize, reload and update itself. It will refresh your phone a couple of times. Don’t worry, this is normal.
4. After it updates, go back in and select the “End User” option. Then browse around! It’s like the black market of the iPhone community! Fun!
DISCLAIMER:
This guide is not meant for people who have an unlocked iPhone that they use on a network other than AT&T (or any other official iPhone network). You guys should wait for the official ultrasn0w release which will allow for unlocking your phone under the new firmware. Find more info here: http://blog.iphone-dev.org/
ADDITIONAL DISCLAIMER:
In the very unlikely event your phone borks itself (trust me, it’s really rare, I’ve jailbroken my phone at least 20 times, and it’s never gone belly up), I have to note that jailbreaking is done by your own choice and is your personal responsibility.
Okay, that’s that. All in all, it should have taken under an hour, with most of the time taken up by backing up and restoring. Really, it’s that easy.
Have fun with your iPhone 3G and all of the new features of iOS 4.0 + jailbreaking.