ArcEmu

ArcEmu is the first emulator for Apple Watch and also runs on iPhone and iPad, delivering a comprehensive gaming experience across all your Apple devices. It uses the fast mGBA core to emulate Game Boy, Game Boy Color, and Game Boy Advance, with precise controls and flexible input options across devices.

ArcEmu supports online multiplayer via Game Center for up to 4 players, save states that sync across devices with iCloud, ZIP and ROM import from iPhone, and a cheats database. It does not include any games or ROMs; you import your own ROMs. The project emphasizes cross-device play, cross-platform save sharing, and broad compatibility with Apple Watch Series 3 and newer, while not being affiliated with Nintendo.