How can I tell iTunes to not back up my old iPhone 3GS when I plug it into iTunes
I have an iPhone 4S, and an old 3GS I'm using as an iPod touch. I asked the salesperson at the apple store whether having my old iPhone backing up in iTunes would cause problems, since iTunes only stores one backup. She said probably, and that I should set iTunes to stop backing up my old phone when I plug it in to sync.
a) Is this correct, that a backup of my old 3GS will overwrite my last backup of my new 4S?
b) Is there a way to turn backups off for a specific device (short of just remembering to click the X when the backup starts)?