Transferring app from iPhone to iTunes

Is there a way to transfer an app from the iPhone to iTunes? For instance, I have NetShare on my iPhone and it is no longer available in the iTunes store but I'd like to have it in iTunes for safekeeping just in case. Each time I sync, it says that apps that are on the iPhone but not in iTunes are being transferred but I never see them in iTunes.

Rayfire said:

When you connect your iPhone to iTunes, right click the name of your iPhone and select Transfer Purchases from the iPhone. See if that works. Oh wait that's on a PC advice if I may add.

Click to expand...

Thanks. On my Mac, that is not working for some reason...does that function work for others?