While there is no official Call of Duty: Modern Warfare release for the PSP, you can enjoy a similar experience through the official PSP title or fan-made homebrew projects. Official PSP Call of Duty Game
: Due to the PSP's single analog stick, looking is handled via the face buttons, though it includes strong auto-aim to assist. Better "Modern" Options & Mods call of duty modern warfare psp iso better
If you are looking for a "Modern Warfare" experience on PSP via an ISO, you are likely looking at (often built on the Counter-Strike PSP engine) or attempting to run the original Call of Duty 4 While there is no official Call of Duty: