If you have any iPhone I’m sure you’ve seen this message when trying to upgrade iOS. Not very helpful is it? Each time I get it I go searching around the iTunes UI for a way to do it. Finally I end up Googling to find the answer: File->Devices->Transfer Purchases
Apple, how about adding a button to fire off this process? The cancel button is pretty useless here. Or, I don’t know, make the Sync operation do it by default! Why would I not want my purchases synced to my account?