How to reinstall GTA VC with all saves on iOS 7?

I installed GTA Vice City on my iPhone through… Um… Illegal, kind of ways. Then, I added some music to my iPhone on iTunes. Of course, I can't play the game then. I still have the game here, but I'm afraid that my saves will be deleted after deleting the game. How can I reinstall this with all saves?

It's your fault for downloading a paid game for free.

They need the money.

I'm not sure how you managed to download the game "illegally", but… F!#&$ off.