FAQ - JoyCon Droid

Why do I need Android 9 or higher?
Bluetooth HID Profiles were introduced in Android 9 which allow your device to function as a gamepad, mouse, keyboard, etc. You cannot do this on lower Android versions. Use the Tester app to check if you have it.
Why do I need root?
Switch firmware version 12.0.0 and up has changed the functionality behind controller connection and input. It now has a Bluetooth Device Class check for initial pairing requests which checks if your device is a Gamepad or others. You need to be rooted with Magisk to use the Bluetooth++ module and change your device class to 002508 or to change your device’s Bluetooth MAC address to a real controller you have already paired with the Switch. Click here for how to use Bluetooth++. Root is also needed if you want to try to enabling support for Bluetooth HID Profiles. 
Magisk is not necessarily required. You can be rooted with something such as SuperSU as well and would just have to manually install or edit your files by accessing them with root privileges. Magisk is recommended and usually easier though since you can just install a module and it will install those files automatically. 
The JoyCon Droid app itself does not need root, but the workarounds needed to get paired with the Switch need root.
How can I root my Android or install custom ROMs?
Every device is different and may use a different set of instructions with unique files to gain root access. Some phones have a difficult process to unlock the bootloader which is needed to flash a custom recovery and install custom ROMs or root with Magisk. Some phones might also be impossible to unlock or root. The best thing to do is search your device’s exact model on XDA Developers Forums. Some more information can be found here.
This process usually erases everything on your phone, may cause issues with certain apps due to SafetyNet Attestation, etc. so make sure to backup everything important or just use a spare Android device. You can end up with a non-functioning brick if you do not follow the instructions for your specific Android device carefully.
The Tester app failed. Can I still enable support for Bluetooth HID Profiles?
Yes, you can try using the Bluetooth HID Enabler Magisk Module. This still requires Android 9+ and a rooted phone with Magisk to install modules. This module can help for devices that usually have it disabled such as OnePlus, Motorola, Huawei, LG, Sony, and Xiaomi. Restart your device after installing and enabling the module, then try the Tester app again.
I'm unable to install JoyCon Droid from the Play Store?
Some devices like above are blacklisted since they normally lack support for Bluetooth HID Profiles. If you actually pass using the Tester app, you can install the APK from GitHub here.​
Is it safe to change my Android's Bluetooth Device Class?
There is always some risk to rooting your phone and modifying system settings. Bluetooth++ will save your default Device Class so you can always reselect it after you're done playing with your Switch. It is however encouraged to make backups before doing any of this as a good practice of safety.
Why does my phone keep disconnecting from the Switch?
Disconnect any other Bluetooth devices that are connected to your phone such as headphones, speakers, smartwatches, etc. Try the connection workaround and make sure to save your Android's Bluetooth MAC address in JoyCon Droid Settings. Retry connection by Disconnecting Controller using the status bar notifcation on Android and leaving the Change Grip/Order screen or Restart both your Switch and Android.
It's also possible you have a Samsung Galaxy A50/A51 which is known to give problems with connecting after a Samsung system update. 
Please be aware that the app can be unstable and it can take you multiple tries to get connected properly. 
What is needed to use amiibos?
Bluetooth HID_DEV_MTU_SIZE 512. Most Samsung devices will have this already. LineageOS 16.0 or higher based custom ROMs built after 7th of September 2020 are likely to have this. Make sure to Enable NFC in JoyCon Droid Settings. You can select and change an amiibo .bin file in Settings where it says NFC Binary Path. Go here for more information on using amiibo. [The Patch introduced on 7th of September 2020 is only for the AOSP Bluetooth Stack. If an Android device uses the Qualcomm Bluetooth Stack, HID_DEV_MTU_SIZE is still set to 64. Qualcomm however forked the AOSP Bluetooth Stack.]
My phone doesn't have NFC. Can I use amiibos?
Yes. It does not matter if your phone has NFC or not. amiibos are being sent through Bluetooth.
Where can I get amiibos from?
Since amiibos are copyrighted content, JoyCon Droid cannot help you obtain amiibo .bin files for legal reasons. It is assumed that you are using personal dumped copies of your own amiibos such as from Tagmo.
Some amiibos are not working?
There are certain amiibos which will not work because they require writing data and JoyCon Droid does not yet support this feature. Some examples of this are Wolf Link in Breath of the Wild, Splatoon 2, and many other games that register amiibos.
amiibos aren't working for me?
Once again, amiibos only work with Samsung devices or with a custom ROM such as LineageOS 16.0 or higher, and the custom ROM needs to be built after 2020-07-September because they have a Bluetooth HID_DEV_MTU_SIZE of 512 bytes. If you have this, try other amiibos and try a combination of a REAL Left Joy-Con and a Right JoyCon in JoyCon Droid and also try lowering Packet Rate to 10 pps in JoyCon Droid settings. Please be aware that the app can be unstable and it can take you multiple tries to get connected  properly and "scan" amiibos.
Can I resize the buttons or customize the layout of my controller on JoyCon Droid?
Yes, you can Select and Edit a Custom UI from the menu options of JoyCon Droid. You will also find other custom UI options created by members of the community such as Macros and TAS UI here. You must have an Internet connection to access these Custom UI options.
How do I use a gamepad/controller with JoyCon Droid?
You can connect a gamepad to your phone using USB. You may need a USB OTG adapter. You can’t connect it through Bluetooth due to the way JoyCon Droid utilizes the Bluetooth connection to pair with the Switch. To avoid connection issues, you must also disconnect other devices such as wireless speakers, smartwatches, etc. To Remap Buttons/keys, find Map Buttons in the menu options of JoyCon Droid.
Can I get banned for using JoyCon Droid?
JoyCon Droid has been available from the Play Store for over 2 years and has millions of downloads from users. No one has ever gotten banned yet. There's currently no way that your Switch can tell the difference between JoyCon Droid and a real Switch controller. You should be safe, but there could still be some risk such as if you use Macros or Turbo Controller to cheat in online multiplayer games and someone reports you.
Does this app work with the Switch Lite?
Yes.
After connecting JoyCon Droid successfully, the Switch keeps asking to do a controller update?
If your Switch asks you to do a controller update for a controller from JoyCon Droid, DO NOT do it. It will get stuck. Press Later to skip that popup. If you accidentally pressed Update, simply disconnect the controller by using the Status Bar notification on your phone.
Is there really no way to use a non-rooted Android?
If you have a spare rooted Android phone or a friend with one, you can try the method here. If the Device Class check is ever removed in future Switch updates, that will probably help again but it's not likely that they will remove it.
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