Mame - MAME stands for Multiple Arcade Machine Emulator.
RetroArch - RetroArch is a frontend for emulators, game engines and media players.
Nebula - Nebula is an arcade emulator.
Happy Chick - Happy Chick emulates more than 18 systems all in one APP
Shmupmame - Shmupmame is a variant of the MAME emulator optimized for Shoot-em-up games (Shmups).
OpenEmu - Console and Arcade video game emulator for macOS.