Custom Firmware (CFW)

Custom firmware is community-built software that replaces or augments a device’s stock OS, often unlocking better emulator front-ends, tuning, and features than the manufacturer ships. On many budget retro handhelds it is practically the point, and reputable projects are a big reason a cheap device punches above its weight. The caveats are honest: it can affect warranty, carries some risk if flashed carelessly, and — as always here — it is a tool for running games you legally own, not a route around that.