gbajs3 vs RetroArch

gbajs3 is a free, browser-based Game Boy Advance emulator for modern browsers, with no plugins required. It offers interchangeable mGBA WebAssembly and pure JavaScript gbajs cores. Both cores support a realtime clock. Controls include remappable keyboard bindings and virtual controls for desktop and mobile, alongside mobile interface support and offline progressive web app support. Fast forward is included. Save states and cheat codes work with the mGBA core, while a surface-level assembly debugger is available with the gbajs core. The project also lists a Go server for logged-in users, an Nginx server for content, an admin interface and PostgreSQL support. Self-hosting uses an environment file and Docker Compose. The setup guide says the default admin password is admin and instructs changing it after login. The README marks debugger and server enhancements as unfinished, and GitHub lists no releases.

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.