I recently (and foolishly) upgraded to 1.1.2 on my iPod touch because I wanted to see the non-existent new features it brought. Yes, it gave me the much desired calendar “Add” button and yes, it gave me the useless battery indicator in iTunes, but I already had the Calendar button and had no need for the battery indicator, so I set on my mission to downgrade back to 1.1.1.
I read on some sites that the process was hard to do, with having to download an extra application or input a secret button sequence into the iPod. However this was not the case. After getting my copy of 1.1.1 from Apple’s site, all that was left was to Option + Click on the update button in iTunes, and navigate to the downloaded zip file. This process leaves all personal data and music on the iPhone or iPod Touch, but allows you to downgrade easily and safely.
After the downgrade was complete (which is exactly the same process as an upgrade) I set about re-hacking my shiny little Touch. The hacking process on the older firmware is ridiculously easy. Simply point Safari to jailbreakme.com and click install. This will JailBreak your iPod or iPhone, install the Installer.app and also patch the TIFF exploit, so you get the same security as in 1.1.2. After the installation completed I set about looking for the iPhone apps. I installed the BSD Subsystem and Community Sources from Installer.app and then added http://repo.us.to to the sources manually. This then allowed me to install the iPhone apps from the list of packages.
There are also literally hundreds of community developed apps including games, chat apps, and the AnySim unlock app for the iPhone to allow it to be used on any network. That’s it, happy hacking! (Please Note: Hacking of devices is at your own risk. The above tutorial is simply for educational
purposes only). 
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