- Start iTunes and plug in your iPhone which is running the 1.1.1 firmware.
- Hold down the Sleep and Home button for 10 seconds. Allow the phone to power off, but keep holding down the buttons. After 10 seconds, let go of the Sleep button, but keep the Home button pressed until iTunes sees your iPhone. The screen on your iPhone should be displaying nothing right now.
- iTunes will ask you if you want to restorea. Hold down Option or Alt, I forget which (Shift if you are in Windows), and click restore. When iTunes asks you what file you would like to restore from, navigate to your 1.0.2 folder. You may have to rename that file to .zip and uncompress it. It will begin to restore.
- When it completes, you will get an error. The iPhone will display the yellow triangle on the screen. Leave iTunes open, and run AppTapp. This may give you an error, but you should see the "Activate iPhone" screen after.
- Run AppTapp again. If the iPhone isn't being recognized, restart the computer and then run AppTapp for the second time.
- Congrats! You now have 1.0.2 again! iNdependence and all other modding apps will now work.
UPDATE: Not confirmed yet, but for those having the "incorrect SIM" issue after dowgrading, try this (thanks, Doerr)
Just turn off the phone, take out the SIM card, turn it on, and when its done put it back in.