JPCSP

JPCSP was one of the most advanced early PSP emulators. It made impressive progress and reached good speeds despite being written in Java, a slower language than most emulators use. Java does have one big advantage: its code is cross-platform from the start, so less development time is spent adapting it to specific platforms.

JPCSP runs some commercial games at full speed, an impressive feat for any PSP emulator. It does this by taking full advantage of multi-core CPUs, matching the PSP’s own dual-processor design. Extra cores help further, as they can be left to handle Java’s JIT compiler and the graphics cache.

JPCSP can play hundreds of commercial games, although PPSSPP has since overtaken it in compatibility, speed and features and is the better choice for most people.