I don't know if it's a strange question but how could I run a game made with XNA on the iPhone/iTouch ? Which steps/tools (existing ones or imaginary...) should be used ?
note: The goal is to avoid modifying existing C# code
UPDATE :
If I understand correctly, I must be able to:
1) Run my XNA code on Mono (monoxna or SilverSprite, promising?)
2) Run Mono on iPhone (MonoTouch)
Answer
Not only is it possible but here is a video of someone doing XnaTouch on MonoTouch: First game to IPhone build with XnaTouch (XNA for IPhone)
Here is the mono article about doing it http://www.mono-project.com/MonoTouch