PPSSPP is a PSP emulator written in C++, and translates PSP CPU instructions directly into optimized x86, x64 and ARM machine code, using JIT recompilers (dynarecs).
PPSSPP can thus run on quite low-spec hardware, including stronger ARM-based phones and tablets, as long as there’s support for OpenGL ES 2.0.
PPSSPP can run your PSP games on your PC in full HD resolution, and play them on Android too. It can even upscale textures that would otherwise be too blurry as they were made for the small screen of the original PSP.
Even on modern Android phones and tablets, you can often run at double the original resolution.
PPSSPP is an open source project, licensed under the GPL 2.0 (or later). Anyone is welcome to contribute improvements to the code. Partly thanks to such contributions, PPSSPP’s compatibility is steadily increasing, letting us all play our PSP games on the devices of our choice.