RePlayOS vs RetroArch

RePlayOS is a Linux distribution for emulating classic game consoles, arcade machines, and computers through a streamlined libretro frontend. It is built around Raspberry Pi hardware, with listed support for Zero 2, 3A/B/B+, 4B, and 5B models, and works with LCD and CRT screens. Its DynaRes display engine supports native CRT timings, timing changes, CRT profiles, dual-screen modes, and LCD operation at game refresh rates. The system supports more than 700 controllers and up to six players, plus RetroAchievements in compatible cores and games. Replay Control is a companion web app for browsing games, launching them on a TV, managing favorites, and configuring the system over a local network. Compatible cores can use Link Play multiplayer over that network. Alpha Player handles audio and video files, with Raspberry Pi 5 recommended for movies. A small HTTP JSON API provides local or LAN control when enabled, but uses plain HTTP. The public version is free; the frontend is proprietary, with restrictions on modification, standalone redistribution, and unauthorized commercial use.

RetroArch is a frontend for emulators, game engines, and media players, bringing them under a unified settings system. The RetroArch/Libretro project includes more than 200 cores across those categories. Its menu can group scanned games by system and display thumbnails and animated backgrounds. Common game controllers configure automatically when plugged in, and button actions can also be assigned manually.

Stackable shaders can change rendered graphics or imitate the look of CRT monitors. Built-in netplay supports hosting or joining network gaming sessions, including spectator mode. RetroArch can record gameplay to video files and stream games to Twitch or YouTube. Versions are listed for Windows, Linux, Android, iOS, macOS, and web browsers. RetroArch is free and open source under GPL version 3; the libretro API uses an MIT license. Features differ by platform and store version: the browser edition has lower performance and fewer capabilities than the full version, while Steam lacks Core Updater and thumbnail scraping and offers a selected core set.