backupiosipod-touchrestore
I have just recently upgraded from iOS 4.3.5 to iOS 5.1.1 on my 3rd generation iPod touch, but it seems that my iPod is slower and a little unresponsive, so I want to downgrade back to 4.3.5.
I want to know how to backup the data (mainly game saves) so that when I restore to 4.3.5 my game save is still there.
If you don't need any network activity, I would recommend enabling Airplane Mode overnight.
Failing that, disable bluetooth and/or wifi if they are unnecessary
Disable as much Spotlight search as you can afford to by going to Settings->General->Home Button->Spotlight Search.
Not today.
It looks like the current app asks iTunes to require GPS on iPhone.
iPod Touch and even iPad with GPS are prevented from downloading the app directly and iTunes will not install it.
I don't know why iTunes doesn't tell you what specific devices the app will work on rather than be a little vague about "not compatible with this device".
Best Answer
iTunes will backup the data, but there is another option. You can also bring your game saves back to your downgraded firmware, but it will take some work.
Here is a walkthrough focusing specifically on Angry Birds, but you could use the same process for other games as well.