Lemon

An Android-only Nintendo Switch emulator built for Adreno GPUs.

Website | Main repository | FAQ | Settings guide | Discord

The main repository and the releases live at https://git.lemon-emu.org/lemon/Lemon-Project. This GitHub repository is a mirror. For help or to report a problem, use the Discord.

About | Features | Changelog | Scope | Building | License

About

Lemon is an Android-only Nintendo Switch emulator built for Adreno GPUs. It runs on the open-source emulation core developed by the yuzu community and the projects that followed it, trimmed down to just what's needed to build and run it on a single Adreno-equipped Android device: no Qt/desktop/CLI targets, no multi-platform CI, no Mali/PowerVR-specific code paths.

Started as a personal build for the maintainer's own device(s); builds are now published on the Releases page of Lemon's own server and the app checks for new ones on launch (with the GitHub mirror as a fallback). It's still a small, personal-scale project rather than a community one — there's a Discord for feedback and support, but it isn't actively looking for external contributions; the source and releases are public under the GPL.

Most of Lemon's additions are Android-side features layered on top of unchanged core emulation, plus changes to what gets built, how, and the app's branding/UX. The one exception is savestate: making Quick Save/Quick Load work reliably on real games required real changes to the emulated kernel itself (how a thread parked mid-syscall is captured and restored) — see Features below.

Features

Everything below is specific to Lemon, on top of the Switch emulation it inherits from Eden/yuzu:

• Redesigned interface — a launcher-style library (carousel, grid or list), a quick in-game panel with a live performance card, redesigned Settings, About and Statistics screens, and full controller navigation, including gamepad shortcuts to open the in-game menu.
• Lemon Cheater — a live memory search/edit tool built into the in-game menu, Cheat-Engine style: exact-value and blind (unknown-value) searches over 32-bit integers and floats (a float matches within the precision you typed), refine by increased/decreased/unchanged across passes, direct value editing, and freezing a found address so it stays fixed (infinite HP/ammo/etc.) via a background rewrite thread, without needing a premade cheat code.
• Input macros — record a sequence of on-screen controller presses with their timing and play it back, looped or once, for repetitive farming/grinding or practicing a sequence.
• Quick Save / Quick Load (experimental) — same-session savestate. Required a real fix in the emulated kernel itself: a guest thread parked mid-syscall (waiting on a condvar, an IPC reply, a timer...) lives inside a host fiber whose true resume point isn't in the register/memory snapshot a savestate captures, so a naive restore left it resuming into a world that no longer matched what it expected and the game aborted. Restore now leaves any still-waiting thread's own context and stack untouched, and retries around waits that depend on another guest thread instead of forcing them. Verified working repeatedly on real, demanding titles, but still not 100% reliable in every game/moment.
• Controller layout presets — a "Diseño del mando" entry in the pause menu with one-tap presets (default, big buttons, swapped D-pad/stick) plus quick access to the existing drag-and-resize edit mode, which used to be buried two menus deep with no indication it existed.
• Controller layout per game — move and resize the on-screen controls for one game only, or for all of them.
• Reset all settings — a red card at the bottom of Settings that puts every setting back to a fresh install's defaults, optionally also deleting every game's custom settings. Game folders, storage locations and each game's add-on choices are kept (unless the games' settings are deleted too).
• Website, settings guide and FAQ at lemon-emu.org, in English and Spanish, with a plain-language explanation of every setting.
• Game usage stats — automatic per-game playtime, last-played time and session count, surfaced as a "Continue playing" shortcut on the games list and a sortable ranking on a dedicated Statistics screen.
• Carousel/grid/list browsing with per-card usage badges, favorites, and search/filtering across your library.
• In-app updates — checks Lemon's own server on launch (falling back to the GitHub mirror when it can't be reached), on demand from the About screen too, and can download/install the new APK directly, with no path (missing release, no connection) that crashes the app. A one-time "What's new" notice follows an update.
• Adreno GPU driver manager — install alternate Adreno graphics drivers per game, plus per-game performance presets, frame generation and post-processing options.
• Save data import/export, Amiibo loading, and ad-hoc multiplayer, same as upstream Eden.

Changelog

Full release notes (including Nightly/Experimental prereleases) are on the Releases page. Highlights:

As of v0.3, Nightly and Experimental have been merged into main and retired as separate channels — one consolidated build going forward instead of splitting fixes across three branches.

• v1.0.0 — Lemon has its own home: the code, the releases and the updates now live at git.lemon-emu.org (GitHub is a mirror) and there is a website, lemon-emu.org, with a settings guide and an FAQ. A new interface: launcher-style library, quick in-game panel with a performance card, redesigned Settings/About/Statistics and full controller navigation; the new screens are translated to Spanish. Controller layout per game. Lemon Cheater searches, edits and freezes floats as well as integers. Reset all settings on the Settings screen. GPU Mode is Accurate by default: Fast made textures flicker in some games (confirmed on Garfield and Dragon Ball). Updates come from Lemon's own server with GitHub as a fallback, a Check for updates button on the About screen and a "What's new" notice after an update. Fixes: FIFA's missing player indicators, ball-direction lines, button prompts and text (a texture handle that travels with the vertices could not be followed by the shader compiler, so those draws were silently dropped; draws are now split by texture); FIFA 23 stuck at the splash screen (the network service lacked an Ioctl call); updates and DLC bundled in .nsz files showing the wrong version and no DLC; motion controls on every screen rotation, so they work on foldables and tablets held landscape. Known issue: in FIFA 23 the faces of some players can show wrong colors.
• v0.3.5 — Coming from Eden, Citron or yuzu: Lemon imports your saves (plus keys and firmware if it has none) without opening the other emulator, from the first-run setup or the top of Settings. Android 12 support. The Lemon-Ade driver ships inside the app and is picked automatically on the Adreno 830, with an automatic fallback to the system driver if a game fails to start with it; Lemon-Ade is also first in the driver downloader. Games built for Switch firmware 22.0+ (ZBIC-compressed executables) load. New logo by Madeleine. Fixes: Add-ons toggles flipping other entries while scrolling, GPU-written textures evicted under memory pressure, the update notice never showing, plus several upstream Eden fixes (MK8D/SM3DW local wireless crash, controller-disconnect freeze, SGSR black screen on system screens, UE5 buffer sync races, IPS/pchtxt mods).
• v0.3.4 — Hotfix: the loading screen could stay up forever after a game had started. The check that hides it once the first frame renders shared its message queue with the touch-overlay auto-hide, which clears that whole queue on every screen touch; the check was cancelled and never restarted. The adaptive-performance watchdog had the same problem and is fixed too.
• v0.3.3 — Compressed dumps: .nsz and .xcz load directly. Block-compressed files (the .xcz default) are read in place with nothing written to disk; solid ones are decompressed once on first use and cached for later launches (least recently used entries evicted past 24 GiB). Rendering: added a missing barrier before indirect compute dispatches, compute dispatches are no longer skipped, and fixed crashes on dead compute descriptor slots and when rescaling texel buffer views. A corrupted or truncated pipeline cache is now rejected instead of crashing on launch. The loading screen stays up until the first real frame. Older Adreno devices (Snapdragon 888/865): the custom GPU driver is no longer loaded and unloaded repeatedly. Quick Load validates the whole savestate before touching any memory. Fixed a Lemon Cheater freeze deadlock and an out-of-memory abort when taking a snapshot. The game list scans faster (containers are no longer re-parsed on every query) and no longer races between threads, which could crash or drop updates/DLC. Also includes everything from v0.3.2-nightly.1 below.
• v0.3.2-nightly.1 — Prerelease. Quick Save/Quick Load no longer aborts a restore over a memory region that's legitimately (not corruptly) become partially unmapped since the save; that region is now skipped instead, like an excluded sleeping-thread stack. Fixed a crash on some older Adreno/KGSL devices (confirmed on Snapdragon 888 and 865) importing a custom GPU driver from your own file instead of the in-app downloader — two driver-manager UI labels were each building a full throwaway Vulkan device just to read two strings, and that churn stacked with a real driver reload into several rapid GPU-driver open/close cycles. New app icon and branding (launcher icon, default profile picture), plus a Ko-fi link on the About screen.
• v0.3.1 — Fixed the auto-updater: enable_update_checks defaulted to false, so the update check never ran for anyone who hadn't manually found and flipped a Settings toggle they had no reason to know existed (now on by default); a separate tag-comparison bug meant Nightly-flavored builds' check silently bailed out even once enabled. Renamed remaining "Eden" leftovers to "Lemon" (device/system nickname in Settings > Advanced, plus a few lower-visibility internal identifiers).
• v0.3 — Channel consolidation: Nightly and Experimental are merged into main and retired; a single build going forward. Quick Save/Quick Load now excludes threads asleep on a kernel wait from the restore instead of corrupting their stack/context, making it reliable on real multi-threaded games (previously same-session only, MVP-quality); savestate files shrunk ~3x via sparse-encoding zero-filled memory pages. Fixed a missing Vulkan synchronization barrier between compute-shader dispatches and the draws/copies that consume their output, causing intermittent black rendering artifacts (confirmed on Zelda: Tears of the Kingdom's procedural grass and shadows). Retry custom GPU driver loading instead of falling back to the (on some devices, unstable) system driver after a single attempt, fixing a repeated crash-on-launch pattern confirmed on Snapdragon 888/Adreno 660. Fixed a native out-of-bounds memory-unmap during shutdown that could corrupt state carried over into the next game session. Fixed a crash opening Settings after exiting emulation. Fixed Release builds silently sharing a stale build configuration with the debug-adjacent RelWithDebInfo build type (wrong reported version, unoptimized binary). Controller layout presets (Default/Big/Swapped D-pad↔stick) with one-tap apply from a new in-game menu. Discord and Buy Me a Coffee links on the About screen.
• v0.2.3 — "Continue playing" card and playtime/last-played/session sorting on the Statistics screen; Lemon Cheater freeze/unfreeze with a dedicated "Frozen" view; input macro recorder/player; auto-updater pointed at this repository instead of upstream Eden's.
• v0.2.2 — Game usage statistics (playtime, last played, session count), a new Statistics screen, and per-card usage badges on the games list.
• v0.2.1 — Fixed the Lemon Cheater's context menu appearing behind game cards in Carousel view.
• v0.2 — Added the Lemon Cheater live memory editor, plus assorted bug fixes.
• v0.1 — Initial release.

Scope

• Android only. Every desktop/CLI build target from upstream has been removed.
• Adreno only. Mali and PowerVR GPUs are explicitly out of scope and untested; the app may start on them, but they are not supported (see the FAQ).
• No keys, no firmware. prod.keys and Switch firmware are not part of this repository and never will be — sourcing them from your own legally owned console is entirely on you. Lemon does not touch key derivation, decryption, or DRM in any way; it only builds the emulator app.

Building

Releases are built and published manually (see the Releases page for prebuilt APKs). A GitHub Actions workflow exists to verify the build still compiles, but it's manually triggered (workflow_dispatch) and only runs on the GitHub mirror. To build locally:

Dependencies: Android Studio, NDK 27+ and CMake 3.22.1 (installable from Android Studio's SDK Manager), and Git.

git clone --recursive https://git.lemon-emu.org/lemon/Lemon-Project.git

Then either open Lemon-Project/src/android in Android Studio and use Run > Run 'app', or from a terminal:

export ANDROID_SDK_ROOT=path/to/sdk
export ANDROID_NDK_ROOT=path/to/ndk
cd Lemon-Project/src/android
./gradlew assembleMainlineRelWithDebInfo

.ci/android/build.sh (used by CI) wraps the same Gradle build with a friendlier flavor/build-type flag interface — run it with --help for details.

License

Lemon, like Eden, is licensed under the GPLv3 (or any later version). Refer to LICENSE.txt.

Special thanks

This project stands on the open-source work of the yuzu community and of the projects that came after it:

• Yuzu
• Eden
• Ryujinx
• Sudachi
• Citron
• Torzu
• Suyu
• Ryubing

And everyone who continues or has contributed to any of them. <3

A very special thank you to Madeleine, who designed Lemon's logo for free and put up with endless rounds of changes with a lot of patience. Thank you, Madeleine! <3

Si te ha gustado mi trabajo puedes invitarme a un café

O si lo prefieres, un Ko-Fi... Gracias!