What doesn't get backed up/needs to be setup again after an iTunes backup & restore?
iTunes does a good job of backing up and restoring all your iPhone data, settings and purchases. It backs up everything that couldn't be downloaded again. There are two ways you could backup your data using iTunes: Transfer purchases to iTunes - This is a very crucial setting that can affect a lot of things. If you don't want to login into each of your apps again after the restore, make sure you say yes to this question (this question will popup as soon as you start your backup process). Saying yes will encrypt your backup with a password. This is where things get tricky. I must have chosen a password the first time I backed up my phone and when I chose to back my phone up again after an year with the transfer purchase option, iTunes somehow did not ask me for a password (it may have remembered my old password). While doing a restore, when I selected that backup, it started demanding the password from me. I had erased all my data and settings from my phone after backing it