Which game is this version 2

I saw someone else just ask this same question, and people were helpful and gave responses. About a year ago I saw this guy playing a game on a mac and I was always interested in what it was and have searched for quite a long time... I would have asked him, but trust me this guy was weird.
The only explanation I have for the game is that he was flying a guy around that was wearing a jet pack. The view was from behind the guy and you could see a decent amount of scenery which was a city he was flying through. I dont think there are many games with guys flying by jetpack so hopefully some of you have seen/payed this?
Thanks

 

They have GTA on computers?? Did not know that. But no it was for sure not GTA of any sort. It might have been possible that the entire game consited of flying a boy around on a jet pack... not sure. If it helps he was playing it on a MB not a MBP but the graphics were still decent, but it must not be very demanding.