I've had an iPhone 4 for a year now. Used it on the same laptop. I recently bought a MBP and when I connected my iPhone to it, it doesn't let me do anything to it. It's basically acting as if this laptop is not the "main" laptop. I can't edit or delete playlists, none of the apps from my iPhone have been put into iTunes etc etc. How can I set it up so that this MBP becomes the main laptop for my iPhone so I can sync, edit, add apps etc.?