Since there is no official ISO, here is what you are actually finding:
Below is a standard description of the game as often found on such platforms: GTA IV (Grand Theft Auto 4) - PSP/PPSSPP Edition Grand Theft Auto IV (GTA 4) Pspiso.club Gta 4
: Small fan-made demos that recreate specific Liberty City locations. Why the Hype for GTA IV in Liberty City? Since there is no official ISO, here is