GearSystem
Gearsystem is a highly accurate, and cross platform SEGA Master System emulator. Written in C++, the developer has managed to make the emulator highly portable, allowing it to be ran on Windows, Linux, Mac OS X, Raspberry Pi and iOS.
It features a highly accurate Z80 core that even implements functionality that was never properly documented for the core, allowing it to emulate games perfectly, even down to there little quirks. GearSystem also has support for multiple mappers, so its able to support the plain SEGA cartridges, Codemasters Cartridges and just ROM only cartridges.
Gearsystem also features highly accurate VDP emulation, including accurate timing.
Gearsystem is one of the most formidable emulators you can get for the SEGA Master System, and also one of the most portable emulators you can get for the system.