RetroArch has been ported to many platforms. RetroArch runs programs converted into dynamic libraries called libretro cores, using several user interfaces such as command-line interface, a few graphical user interfaces (GUI) optimized for gamepads (the most famous one being called XMB, a clone of Sony's XMB), several input, audio and video drivers, plus other sophisticated features like dynamic rate control, audio filters, multi-pass shaders, netplay, gameplay rewinding, cheats, etc. It is the reference implementation of the libretro API, It is licensed under the GNU GPLv3. RetroArch is a free, open-source and cross-platform front-end for emulators, game engines, video games, media players and other applications.