PPSSPP is a popular emulator for playing PlayStation Portable (PSP) games on various platforms, including Android, iOS, Windows, and Linux.
You're looking for a GTA San Andreas PPSSPP ISO file download. Here's some information to help you out: Gta San Andreas Ppsspp Iso File Download
Grand Theft Auto: San Andreas is not a native PSP game, but it can be played on PPSSPP using a PSP-optimized version of the game or a port. PPSSPP is a popular emulator for playing PlayStation