I received my iPhone 4 and activated it, thus my older 3G shows "no service." Can it be used like a iPod Touch? How will it be when I sync with my current iTunes (apps and all) since I have the iPhone 4 on that computer/account. I don't mind renaming my old iPhone and manually syncing what I want. And since I don't have 3G from AT&T due to no service, I still have my wifi at home and around. Can I safely connect my no service 3G to wifi and use the net, email, etc. without any charges from AT&T?