Well you can just buy them from the market place. Not sure what the best gba emu is, but I use "My Boy", since that one was highly rated. It works good enough. There is a PSP emu that's called "PPSSPP" that is continually improving and free. This emu is the go to PSP emulator on the PC as well. I saw I could run Crisis Core at decent speeds now, while I couldn't before. DraStic is a great DS emulator. I use ePSXe for PSX games not sure if it's the best one for android, but the emulator is great on PC.This is awesome.
Is there an Android equivalent? Anyone know?
Teach me. I'm new-ish.


