Play! vs RetroArch

Play! is a free, open-source emulator for PlayStation 2 games, with builds for Windows, macOS, Linux, Android, and iOS, plus an experimental browser port. Its high-level emulation means a BIOS is not required, and the project says users do not need custom settings to fix specific games. Games can be played by inserting a disc; desktop builds also offer command-line options for disc images, ELF files, arcade games, save-state slots, and fullscreen mode. The Play!.js browser version supports ISO, CSO, CHD, ISZ, BIN, and ELF files, but is not intended to run every game supported by desktop and mobile builds. Play! has preliminary support for Namco System 246 and 256 arcade games; release notes described 246 support as desktop-only. A compatibility tracker lists game statuses from Nothing to Playable. On iOS, playing requires JIT code generation, with device, jailbreak, or alternative JIT requirements documented by the project. Automatic JIT activation through AltServer requires it to run on the same network as the iOS device.

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.