Why Wasn't GTA IV Released on PSP?

Technical & strategic reasons:

• Hardware gap: PSP (333 MHz MIPS, 64 MB RAM) couldn't handle RAGE Engine's streaming world, physics, NPC density.
• Storage: UMD 1.8 GB vs. GTA IV's ~16 GB (360/PS3). Heavy compression would ruin fidelity.
• Focus: Rockstar Leeds built Chinatown Wars (2009) for PSP/DS — top-down, stylized, designed for handheld limits.
• ROI: PSP install base declining (DS/PSP → 3DS/Vita transition); resources went to Episodes from Liberty City (360/PS3/PC DLC).

Chinatown Wars is widely considered the better handheld GTA—play that instead.