I'm guessing he runs Nitdroid. Emulation works pretty much perfect with it. Not sure how Emumaster handles it.

ePSXe is available on Android now (the greatest PC PSX emulator) and it runs most PSX games flawless. Maybe he's running FPse though. I find ePSXe much better. Simpler but better. I have it on my Nexus and it's awesome.