PPSSPP
PPSSPP is an up and coming PSP emulator with the aim of speed and portability. Development is ongoing and is still in an alpha state, but progress is fast and many games already run great under both Windows and Android (aswell as about every other OS out there).
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Audio
For most audio, you'll need some method of decoding ATRAC3+. FFMPEG plans to cover that, but for now you need at3tool or SonicStage. Currently the master branch doesn't support either, but this pull and the builds linked there do.
