I made the mistake of upgrading my iPod Touch 2g (MC Model) to iOS4 without having had any of the 3.1.2 or 3.1.3 SHSH blobs saved to Cydia. If you don’t have those blobs saved, you can’t downgrade from IO4.
Until yesterday there wasn’t a jailbreak for the MC iPods. @comex on Twitter released an “in-device” jailbreak for all devices (except iPad 3.2.1, which apparently is buggy and being worked on). By “in-device” I mean that all you need to do is go to http://jailbreakme.com in Safari on your device to jailbreak it. No fiddling with Windows or Mac apps, and it seems to work for most people.
The iPod Touch 2nd generation devices have multitasking and background support disabled, supposedly for performance reasons. I’ve enabled them both following the instructions I’ll put in this post and I have to say that both multitasking and background support work just fine. I’d even venture to say that the native multitasking is faster than when I was using Backgrounder installed via Cydia.
So, here are the steps to jailbreak your iPod Touch 2g (MC model) and enable multitasking and background support.
For battery percentage support, download the correct file in step 5 and follow the instructions for editing General.plist in Update 3 at the bottom of the post.
IMPORTANT: Plug your iPod into your computer and sync via iTunes. Always take a backup before trying anything like this so you have something to restore to! Also, I think this jailbreak is supposed to be done on an un-jailbroken device. I’m not sure what happens if you try running this on an iPod that’s already jailbroken.
1. On your iPod touch, load Safari and go to http://jailbreakme.com. If that site is overloaded, you can also try http://jailbreakme.modmyi.com.
2. Slide the slider bar on that page to the right to begin the jailbreak process. First it will download some files and then it will apply the jailbreak. This took a few minutes on my iPod, so please be patient. The download servers for the jailbreak have been hammered since yesterday. If you end up at a screen with a purple background and it does nothing else, reboot your iPod and try it again. I did have to do this reboot trick to get the download of the jailbreak to work.
3. When the jailbreak is done, you’ll see a message saying that Cydia has been added to your home screen. At this point, you can exit Safari and reboot your device.
NOTE: When I reboot my iPod after the jailbreak, I get a small line of multicolored pixels on the top of the display. This doesn’t seem to hurt anything, and as soon as everything is booted that line goes away (at least for me). So I’m just ignoring it. I rarely ever reboot my iPod anyways.
4. This step is optional. At this point you have a jailbroken iPod. If you want to be able to install .ipa files, launch Cydia on your iPod, go to Manage and then Sources, hit Edit and then Add and enter http://cydia.hackulo.us. When you’re finished adding that repository, search for AppSync and install it. Make sure you install the AppSync version for 4.0! Once that’s done you can install any .ipa file.
5. To enable multitasking and backgrounds, you’ll need to replace a file on your iPod. Download N72AP.plist by clicking HERE. I got this file from http://devonharvancik.com/plist.html which includes instructions on how to use SSH to replace this file. However, the site appears to be down at the moment, and I’m going to provide instructions on how to use iPhoneExplorer to replace this file, rather than installing and using SSH.
NOTE: The plist file has a different filename on some devices (starting with N8 in the filename). I only have a copy of N72AP.plist for 2nd generation MC model.
NOTE 2: If you would like battery percentage support as well, download THIS copy of N72AP.plist instead. This copy has all 3 options enabled. If you want to enable battery percentages, you’ll also need to edit /var/stash/Applications/Preferences.app/General.plist. Please see Update 3 for instructions on editing the General.plist file.
6. Download and install iPhoneExplorer (http://www.macroplant.com/iphoneexplorer/). I have only used the Windows version, so instructions will be for Windows. I imagine the Mac version is similar.
7. Plug your iPod into your computer and run iPhone Explorer. You should be prompted to select the root directory when you first run iPhone Explorer. If you’re not prompted, you can go to File and Select Root Directory. Since your iPod is now jailbroken, you should choose “/” as your root directory and click OK. You should see your “iPhone Root Directory” listed, with many subdirectories.
NOTE: Be careful what you do here as you’ve now mounted the entire filesystem on your iPod. Random clicking and deleting of files will surely brick your iPod, so use caution!
8. In iPhone Explorer, browse to System->Library->CoreServices->Springboard.app.
9. iPhone Explorer supports dragging and dropping files. So open up an Explorer window and create a backup directory. It doesn’t matter where you put this as long as you remember where it is. This should NOT be the same directory where you put the downloaded copy of N72AP.plist (because then you’ll overwrite your downloaded copy with the normal version from your iPod). Once you have your newly created backup directory open in Windows Explorer, drag the N72AP.plist file from iPhone Explorer into your backup directory (just so you have it if you ever need it).
We’re also going to delete a few PNG files that will greatly speed up the Home screen once backgrounds are enabled. Drag and drop the following files from iPhone Explorer into your backup directory on your computer:
This should be all the PNG files that have filenames starting with “Wallpaper”. I have noticed no difference in display quality with these files gone, but I have noticed a huge increase in speed when they’ve been removed.
10. Now in Windows Explorer, browse to the directory where you saved the downloaded copy of N72AP.plist. Drag and drop that downloaded file into the SpringBoard.app directory in iPhone Explorer. Once the file is copied, and iPhone Explorer has finished syncing, delete those PNG files from your iPod by right clicking on each in iPhone Explorer and clicking Delete.
11. Once again reboot your iPod.
At this point you should have a jailbroken iPod Touch 2G that is able to install any .ipa files and has multitasking and backgrounds enabled. To multitask, open an app and double click the Home button. To set a background, use the Photos app.
You should also download TinyUmbrella (http://thefirmwareumbrella.blogspot.com/) and save your 4.0 SHSH blobs. It’s very likely that Apple will fix the bug that’s being used in the latest jailbreak. If you save your SHSH blobs to your computer, you should be able to jailbreak even after Apple fixes the bug.You can also do this from your iPod in Cydia.
Update: If something happens and it looks like your ipod is bricked, try rebooting. If that doesn’t work, you’ll probably have to restore via iTunes and try again. I have no idea why someones iPod would get bricked unless they followed these instructions for something other than an iPod Touch 2nd generation MC model, which is what this guide is written for. I don’t have any other devices, so I can’t say if this would work or not. TRY AT YOUR OWN RISK.
Update 2: When you set a custom lock screen, it only shows up when you don’t have the iPod plugged in. Plugging it in seems to switch it to the standard battery screen. Unplugging it (at least on mine) brings up my custom lock screen. Since I don’t have a newer iPod that natively has backgrounds turned on, I’m not sure if this is normal or not. Doesn’t bug me, as I only plug it in for syncing and charging.
Update 3: Some people have asked how to manually edit the N72AP.plist file and how to enable battery percentages. These plist files are binary, so you need to use a plist editor. If you’re on a Mac, Apple’s PlistEdit Pro is probably the best app to use and can be found HERE. For Windows, I used iPodRobot which can be downloaded HERE. Basically you want to open up iPhone Explorer, drag the N72AP.plist file to your local directory, and then open it with the plist edit. The keys that have been added to the capabilities section to add support for multitasking and backgrounds (and optionally battery percentages) were:
To fully enable battery percentages, once again in Iphone Explorer browse to /var/stash/Applications/Preferences.app. Drag and drop the General.plist file to your computer and edit it using one of the editors linked above. Search for the word cellular-data. That section will look like this:
Make that section look like the following instead:
Once you’re done, save the file and drag General.plist back into the /var/stash/Applications/Preferences.app directory. If you manually modified the N72AP.plist file, drag it back into System/Library/CoreServices/Springboard.app directory. Then reboot your ipod.
Once you’ve changed both the N72AP.plist and General.plist files for battery percentage support, after your ipod is rebooted go into Settings and then General. You’ll have a new menu option named Usage which you can use to turn on the battery percentages.
Clayton Braaschs Blog (FAQ on jailbreakme)