Sounds like he wants to control his iPhone with his Mac. I don't know how honestly. Would be a neat feature. I remember wanting to do it a couple of times.
I'll just drop this in as well; because I have stated this several times and each time it has been shot down.
I would like to see a connection (via WiFi, Bluetooth or USB) between the iPhone and OSX. The ability to read texts, use the speakers & microphone in calls or just notifications would be brilliant.
Music Remote is also available. It seems to have more features than just skip and rewind. Looks like you can view playlist and all that jazz. It's $3.99 though. There's only one written review saying it doesn't work on the iPad and 9 one star reviews. It doesn't look promising, but I can't find anything negative regarding the iPhone specifically.