Frequently asked questions

An Android device with a Snapdragon (Adreno) GPU running Android 12 or newer, plus your own games, prod.keys and firmware dumped from a Nintendo Switch you own. Lemon does not include or provide any of them.

Lemon is built for Adreno GPUs, and that is the only family it is tuned and tested for. Other GPUs (Mali, PowerVR…) are not a goal of the project. It is an Android app only; there is no version for iOS, Windows or Linux. See the next question about Mali and MediaTek chips.

It may start, but it is not supported. Lemon does not block other GPUs: the app installs on any 64-bit ARM device with Android 12 or newer. But it has only been built, tuned and tested for Adreno, and the code that was specific to Mali and PowerVR was removed from the project.

If you try it on a Mali (including Arm Immortalis, found in many MediaTek and other chips), PowerVR or Xclipse GPU, expect this:

• It uses your phone's own Vulkan graphics driver. The GPU driver manager and the bundled Lemon-Ade driver are Adreno-only, so they don't appear.
• The result depends a lot on that driver and on the game: more graphical glitches, crashes or low speed are likely.
• We can't test on those devices, so problems that only happen there may not get fixed.

If you want to try anyway, install the latest system update, start with a low resolution and one game at a time. When you report something in the Discord, say the phone and GPU model; the device overlay (Enable Device Overlay, with Show Device Model, Show GPU Model and Show Driver Version) displays them.

The first-run setup walks you through it: Install prod.keys and Install firmware. The firmware has to be a ZIP file. You can do the same later from the settings.

Keys and firmware must come from your own console and should be from the same version. Games from newer firmware need newer keys.

Use Add game folder and pick the folder where your games are. Lemon scans it and fills the library. It reads NSP and XCI files and also compressed .nsz and .xcz files directly.

If the list stays empty, check that you selected the right folder and that the keys are installed.

Use Install game content and choose the update or DLC files. Installing base games this way is not allowed, to avoid conflicts; base games just go in your games folder.

If an installation fails, make sure the files are valid and that prod.keys is installed.

Yes. If you come from Eden, Citron or yuzu, Lemon can import your saves (and your keys and firmware, if it has none) without opening the other emulator. You'll find it in the first-run setup and at the top of the settings.

Yes. The first time a game shows a new effect, Lemon has to prepare it (this is called compiling shaders), and that can cause a brief hitch. Lemon keeps what it prepares, so the same effect should not stutter again. Keep Disk shader cache turned on so it is remembered between sessions.

In order, from the least to the most invasive:

• Lower the Resolution in Settings → Graphics. It is the setting with the biggest effect.
• Turn on Force maximum clocks (Adreno only). The phone may get warmer.
• Close other apps running in the background.
• Try another graphics driver for that game, from its properties.

The settings guide explains what each option does.

Connect it by Bluetooth or cable as you would to any Android device. Lemon detects it. If the buttons are not where they should be, open the controller settings and use Auto-map a controller, or assign each button by hand. You can hide the on-screen controls automatically when a controller is in use (Hide Overlay on Controller Input).

Open the in-game menu and choose Edit overlay. Drag a button to move it and long-press to resize it. When you finish, Lemon asks whether the layout is for this game only or for all of them.

Yes, Lemon uses your device's gyroscope and accelerometer. From version 1.0 they follow every screen rotation, so they also work on foldables and tablets held in landscape.

From the in-game menu, Quick save state stores the exact moment you are in and Quick load state brings you back to it. It is experimental: it works in demanding games but not in every game at every moment, and it only keeps the state of the current session. Keep using the game's own save as well.

It finds a number in the game's memory so you can change it (lives, coins, health…). Open it from the in-game menu, then:

1. Pick Integer for whole numbers or Float for decimals.
2. Type the value you see on screen and press New search.
3. Change the value in the game, type the new one and press Refine. Repeat until few results remain.
4. Tap a result to write a new value. The padlock keeps it fixed.

If you do not know the value, use Blind search and then Increased, Decreased or Unchanged. Freezing the wrong address can make a game misbehave or crash.

Lemon can host and join multiplayer rooms (ad-hoc play and lobbies). To use public lobbies you set a username and a web token in the system settings. Nintendo's own online services are not part of the project.

Put the settings back to the defaults of a fresh install. Open Settings and press the red Reset all settings card at the bottom. Most odd behaviour after trying many options comes from a setting that was changed and forgotten, and this removes all of them in one step.

Your games, saves, keys and firmware are not touched, and your game folders and storage locations are kept. A box in the confirmation lets you also delete the custom settings of every game, which is the full clean slate. Then try the game again. If it works, change one option at a time so you can see which one caused the problem. If it still fails, tell us in the Discord.

To start over for just one game, open that game's settings and use Reset this game's settings.

Try these, in this order:

1. Check that prod.keys and the firmware are installed and match each other. A game made for newer firmware may need newer keys.
2. Check that the game file is complete and not damaged. A new dump is the best proof.
3. Try another graphics driver for that game, from its properties. Lemon already falls back to the system driver by itself when a game fails to start with the bundled Lemon-Ade driver.
4. If it keeps happening, tell us in the Discord with the game name, your device and the build number from About.

Install prod.keys and the firmware (see "How do I install the keys and the firmware?"). Newer games need newer firmware and keys than older ones. Without keys, Lemon can't open most commercial games.

Check that your keys and your firmware come from the same version. Keys are sometimes published with the wrong version label (for example, keys for firmware 22.x labeled as 23), and then the Mii data cannot be read. Try a matching keys and firmware pair.

Open Settings → Graphics → GPU Mode and choose Accurate. Some games flicker in Fast mode and are stable in Accurate. Accurate is the default since Lemon 1.0, so this mostly concerns installs that were switched to Fast earlier.

Accurate can cost some performance. If a game looks fine in Fast and runs too slowly in Accurate, you can set Fast for that game only from its properties.

In Settings → Graphics, change NVDEC Emulation to CPU. That is what the app itself recommends if a game crashes on cinematics.

Open Settings → Audio. Check that Volume is not at zero and that Output engine is not set to Null (that option turns the sound off). Auto is the safe choice; if there are problems, try another engine.

Open the game's properties and use Save data: from there you can manage, import, export or delete that game's saves. Export a copy before you uninstall the app, change device or delete data, because uninstalling Lemon removes its data too.

The fastest way is the Discord. Written reports can also be sent from the GitHub form. Either way, tell us:

• Device and GPU, for example AYN Odin 3, Adreno 830.
• Android version.
• Lemon version: tap the build number in About to copy it.
• Game and, if you have one, its update version.
• What happens and what you expected.
• Steps to reproduce it.
• Logs and screenshots: in Settings → More options use Share debug logs, and Share crash log if the app closed.

Before you send it, try Reset all settings: it solves many problems on its own.

On launch, Lemon checks its own server for a newer release and offers to download and install it. If the server can't be reached, it checks the GitHub mirror instead. You can turn this off in Settings → Check for Updates, and you can also check by hand from About.

Only from git.lemon-emu.org, this website, or the GitHub mirror. Be careful with other sites that offer "Lemon APK" files: we can't vouch for them.

It is a graphics driver for Adreno GPUs, based on the open-source Turnip driver and adjusted for Lemon. It comes inside the app and is chosen automatically on the Adreno 830, with an automatic fallback to the system driver if a game fails to start with it. You can also install other drivers from the driver manager.

Lemon is free software under the GNU GPL v3 or later; the source code is public. Emulation itself is legal, but you must use your own games, keys and firmware, dumped from a console you own. We don't provide them and we don't help to get them.

Lemon is a small project and is not actively looking for outside code contributions, but feedback and bug reports are very welcome in the Discord. If you want to support it, there is a Ko-fi and a Buy me a coffee page.

In FIFA 23, the faces of some players can show up in a wrong color (red or blue, for instance). It varies from one run to the next. We are investigating it. Player indicators, shadows, lines and text are not affected.

It works on demanding games, but not in every game at every moment, and it only keeps the state for the current session. Don't rely on it as a replacement for the game's own save.