eNDS

A DS emulator for iPhone and iPad, built on the melonDS emulation core.

This repository contains the complete source code of the eNDS app as it is built and distributed. It is published under the GNU GPLv3 (see LICENSE) — the same license as melonDS — so that anyone who receives the app can study, build and modify exactly what runs on their device.

Built with AI assistance

This project was written with heavy use of AI coding assistants (Anthropic's Claude, driven from Claude Code). A large share of the Swift and Objective-C++ in Targets/ was drafted by a model and then read, corrected, tested on real devices and shipped by a human — but it would be dishonest to present it as hand-typed work, so it is said here plainly rather than left for you to guess from the commit log.

What that does not cover: the emulation core. Vendor/melonDS is unmodified upstream melonDS, written by Arisotura and the melonDS team, and no AI touched it.

What eNDS adds on top of melonDS

• A native SwiftUI/UIKit iOS frontend: ROM library (with each cartridge's real banner icon), dual-screen layouts, an on-screen controller with a visual layout/style editor, pause menu, save states and auto-save.
• Real microphone input (blow/speak) resampled to the DS mic rate.
• External display / AirPlay support (TV shows the top screen, the device becomes the touch screen + controls).
• Game Controller framework + hardware keyboard support with remapping.
• .zip / .7z / .gz archive import, cheat codes, display filters, ReplayKit clip recording, per-game profiles.
• A layout that follows the window rather than the device: it reflows on iPad Split View, Stage Manager and continuously resizable windows.

Credits

• melonDS — © Arisotura and the melonDS team, GPLv3. eNDS uses the core unmodified (see Vendor/melonDS, pinned as a submodule to the upstream commit each release builds against).
• FreeBIOS — the built-in BIOS replacement inside melonDS, © Gilead Kutnick (BSD). No proprietary console BIOS, firmware or keys are included anywhere in this repository or in the shipped app.
• teakra — DSi DSP emulation, MIT.
• LZMA SDK (7z extraction) — Igor Pavlov, public domain.
• minizip (zip extraction) — Gilles Vollant, zlib license.

See THIRD_PARTY.md for the full component inventory — including the libraries melonDS itself vendors (blip-buf, xxHash, FatFs, tiny-AES-c, SHA-1) — and Targets/INDS/Resources/Legal/NOTICES.txt for their verbatim license texts, which also ship inside the app (Settings › About › Licenses).

Building

See BUILDING.md. Short version: build the melonDS static libraries with CMake (exact flags documented), then open eNDS.xcworkspace and build the eNDS scheme. No account-specific secrets are needed to build; signing uses your own team.

Releases

Every build of eNDS that leaves this machine gets a tag here — v1.0-b29, v1.0-b30, … — and each tag is the complete corresponding source for that exact binary. The current one has release notes on the releases page. main may carry later work (comment translations, docs) that is not in any binary yet; when in doubt, build a tag.

What ships is what you see here: no ads, no analytics and no tracking SDKs of any kind. The app's privacy policy is at mattiaa95.github.io/privacy.html.

What the App Store build charges for

Said plainly, because reading it in the source is not the same as being told: the App Store build has a paid tier ("PRO"), sold as a weekly or yearly auto-renewing subscription or as a one-time lifetime unlock. It gates save-state slots 2–4, the scanlines display filter and custom background images — nothing else. Emulation, ROM library, controller and layout editing, save slot 1, auto-save, cheats, multiplayer, external display and every other feature are free and ungated, and the first 48 hours after install unlock the gated extras too (INDSHoneymoon.swift).

The gates are ordinary if statements in this repository (EntitlementManager, ProGateAlert) and the GPLv3 gives you the right to build this source yourself with them removed. That is by design: the subscription funds the work for people who would rather pay than compile, it is not a lock.

Legal

• eNDS is an unofficial project. It is not affiliated with, or endorsed by, the melonDS team, and not affiliated with any game console manufacturer. All related console names are trademarks of their respective owners and are used here only to describe compatibility.
• On the INDS prefix you will see everywhere in this source: the project was started under the working name iNDS and the class prefix, folder names, bundle id (com.mls.inds) and StoreKit product ids were never renamed when the app became eNDS. It is a leftover, and it is the obvious thing to be suspicious about, so: eNDS shares no code and no authorship with the earlier nds4ios/iNDS project for iOS. That one wrapped DeSmuME; this one is a SwiftUI/UIKit frontend over melonDS, and every line of it is in this repository for comparison.
• Parts of the on-screen controller, layout editor and purchase UI were ported from iGBA, the author's Game Boy Advance emulator, and the comment headers of those files say so. That code is the author's own and is published here under the GPLv3.
• eNDS does not include any games and does not link to ROM sites. Play only backups of cartridges you legally own.