I have an iPhone 3G (16GB), and just got a 3GS on PAYG (32GB). I also just got a touch (8GB) free with my Apple order. I want to sync them all to my MacBook, but I want to put different apps, music and films on each. They are all for my sole use, so I don't want to have to set up different accounts. But if I just plug them in, can I choose what to sync as the device is backing up by using the checkboxes, as I can currently with my iPhone 3G? I don't want to do that and find I've changed anything on the 3G, as this is set up just the way I want it. Please help me quickly, as I need to check my new devices work!