Initially, VGS emulator was made for Mac, but it was later updated to accommodate windows PC. Connectix is the developer of VGS emulator. GBA Emulation on mobile devices became so much popular these days, imagine it is like you are holding a real Game Boy Advance gaming. There are plenty of cool GBA emulators for Mac OS users and here are some of those OpenEmu Boycott Advance 0.4.0 mGBA 0.5.0 Visual Boy Advance M 0.1 GBA Emulators for Android.