NDS Music Player

A cross-platform Nintendo DS music player built with Kotlin Multiplatform. Load any .nds ROM and browse, search, and play its full soundtrack — on iOS, Android, and desktop.

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Download

Platform	Link
iOS (App Store)	Download on the App Store
Android (Google Play)	Get it on Google Play
Desktop (macOS / Linux / Windows)	GitHub Releases

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Features

• Open any .nds ROM — drag-and-drop or use the file picker on every platform
• Browse the full soundtrack — tracks are grouped by SDAT sound archive within the ROM
• Search — filter tracks instantly by name across all archives
• Full playback controls — play, pause, resume, stop, next, and previous
• Configurable loop count — choose how many times each track loops before advancing
• Auto-advance — plays the next track automatically when one finishes; silently skips unplayable tracks
• Lock screen & Now Playing — artwork-free Now Playing card with remote controls on iOS
• Background audio — keeps playing when the screen is off (iOS)
• High-quality audio — powered by FluidSynth for faithful SF2 soundfont rendering

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Tech Stack

Layer	Library
UI	Compose Multiplatform 1.10
Architecture	Kotlin Multiplatform + ViewModel + Clean Architecture
NDS parsing & MIDI generation	kotlinds
Audio engine	fluidsynth-kmp — FluidSynth wrapped for KMP
Dependency injection	Koin

How it works

1. Parse — kotlinds reads the ROM binary, extracts all SDAT sound archives, and exposes the track list
2. Convert — each track is converted on-demand to a standard MIDI file + SF2 soundfont
3. Render — fluidsynth-kmp feeds the MIDI and SF2 to FluidSynth, producing high-quality PCM audio on all platforms

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Building from Source

Prerequisites: JDK 17+, Android SDK, Xcode 16+ (for iOS)

git clone https://github.com/nathanfallet/nds-music-player
cd nds-music-player

Android

./gradlew :composeApp:assembleDebug

Desktop (JVM)

./gradlew :composeApp:run

iOS

Open iosApp/iosApp.xcodeproj in Xcode and run on a simulator or device. Or via Gradle:

./gradlew :composeApp:embedAndSignAppleFrameworkForXcode

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Project Structure

composeApp/
├── commonMain/       # Shared UI, ViewModel, domain logic, AudioPlayer
├── iosMain/          # iOS audio session, Now Playing, lock screen controls
├── androidMain/      # Android entry point
└── jvmMain/          # Desktop entry point
iosApp/               # Xcode project / Swift entry point