Game Boy Advance and Nintendo DS, emulated entirely inside a web browser — including full support for iPhone and iPad, where it installs to the Home Screen and runs fullscreen like a native app.
This is a merge of two projects:
- ds-anywhere — melonDS compiled to WebAssembly via Emscripten, with a Preact/Vite frontend. Provides the DS core.
- gba.js.org — a web frontend around the IodineGBA JavaScript core. Provides the GBA core.
Drop in a .gba or .nds file and the app detects which system it is and boots
the matching core. Your files are read in the browser and never leave your
device — there is no upload, and no server ever sees them.
| Game Boy Advance | Nintendo DS | |
|---|---|---|
| Core | IodineGBA (JavaScript) | melonDS (C++ → WebAssembly) |
| Boot | open-source replacement BIOS (GPLv2) | DraStic FreeBIOS (clean-room) |
| Display | 240×160, nearest-neighbour upscale | dual screen |
| Saves | in-browser (IndexedDB) | in-browser (IndexedDB) |
The DS core already ran on desktop; iOS needed real work, because mobile Safari behaves differently in several ways that break naive emulator frontends:
- On-screen gamepad — multitouch, built on Pointer Events rather than click handlers, so you can hold a direction and press a button at once. The D-pad supports sliding your thumb between directions without lifting.
- Audio unlock — iOS starts
AudioContextsuspended and only lets you resume it inside a real user gesture, so sound is armed on first touch. - Safe-area layout — controls respect the notch, the Dynamic Island, and the
home indicator via
env(safe-area-inset-*). - No zoom — double-tap and pinch zoom are suppressed on the play surface, and form fields are ≥16px so Safari does not force-zoom on focus.
- Wake Lock — the screen will not sleep mid-game where supported.
- PWA install — Add to Home Screen gives a fullscreen, offline-capable app. The WebAssembly is precached, so it runs with no network at all.
This project ships no ROMs and no copyrighted BIOS files, and it never will.
Writing an emulator is lawful — see Sony Computer Entertainment v. Connectix (9th Cir. 2000) and Sega v. Accolade (9th Cir. 1992). What is unlawful is distributing copyrighted ROMs and firmware. So:
- Games come from you, at runtime, from your own device.
- The GBA core uses the open-source GBA BIOS replacement from ez-me/gba-bios (GPLv2, VBA-M / Normmatt lineage) — hand-written ARM assembly and C, not a dump of Nintendo's BIOS. IodineGBA has no high-level-emulation path, so a BIOS image is mandatory; the only question is whose, and this one is free software with public source.
- The DS core uses FreeBIOS, a BSD-licensed clean-room reimplementation written from public documentation and explicitly not derived from Nintendo's BIOS.
.gitignoreblocks ROMs, saves, and BIOS blobs from ever being committed.
The upstream gba.js.org repository shipped 104 commercial ROMs and Nintendo's
GBA BIOS, and was structured as a catalog of them rather than as an emulator you
supply files to. All of it was removed, the ROM-catalog loading path was replaced
with user-supplied file loading, and this repository was created with fresh git
history so that none of it survives in past commits.
Full details, component licensing, and a file-by-file record of what was removed:
see NOTICE.md and docs/REMOVED_MANIFEST.txt.
GPLv3 — see LICENSE. The project incorporates melonDS (GPLv3),
IodineGBA and XAudioJS (MIT, © Grant Galitz), DraStic FreeBIOS (BSD-3-Clause,
© Gilead Kutnick), and the ez-me/gba-bios GBA BIOS replacement (GPLv2, shipped as
a standalone data file rather than linked). MIT and BSD-3-Clause are
GPL-compatible; every component keeps its own copyright notice. See
NOTICE.md.
Not affiliated with, authorised by, or endorsed by Nintendo. Game Boy Advance and Nintendo DS are trademarks of Nintendo Co., Ltd.