EmulatorJS vs Zeta

EmulatorJS is a free, open-source frontend for RetroArch that lets a site owner embed an emulator in a web page. The project provides a code generator, and says the resulting embed can be added with a few lines of code. EmulatorJS uses RetroArch’s libretro cores to run games. Its supported systems documentation includes NES, Nintendo 64, PlayStation, PSP, Sega systems, and Commodore systems, though the project warns that this list may be out of date. Built-in options allow customization, and multiple languages are supported. The project describes EmulatorJS as a library or plugin rather than a standalone website, and it does not provide a Docker container. A public CDN offers paths labeled stable, latest, and nightly. The listed platforms are web, Android, iOS, and self-hosted. Pages must be served through a web server; opening an HTML file directly is unsupported. Threaded cores may improve performance, but need SharedArrayBuffer enabled through COOP and COEP response headers. The 4.3.0-pre release is marked as a prerelease and is discouraged for production use where stability is needed.

Zeta is an iPhone emulator for playing games from a range of classic systems on modern devices. It supports iPhones running iOS 16.0 or later; iPad and Mac are not supported. Users can drag game files into the app or select a library folder through its file browser, after which Zeta recognizes games and displays cover art. Listed systems include Nintendo 3DS, DS, Wii, GameCube, Game Boy, PlayStation 2, PSP, PlayStation, Sega Dreamcast, and Genesis. Gameplay features include manual and automatic save states, speed-up to 5×, cheat codes, custom controls, one-tap combos, skins, filters, and screenshots. Bluetooth controller support covers Xbox Wireless, PlayStation DualShock and DualSense, Nintendo Switch Pro, and MFi-certified iOS controllers. The app also lists multi-controller play, link play, AirPlay casting, and a console mode. The free plan includes core emulation, ROM loading, save states, basic controller support, and screen recording. Premium options are a monthly subscription or one-time purchase, with prices shown in-app or in the App Store.