If your gear (keyboard, midi controller, audio interface etc..) is driverless and class-compliant, then you should be able to use it with the Sunday Keys App.
Popular hardware from many manufacturers is class-compliant and should be plug-and-play. If you’re not sure if your hardware is class-compliant, consult the user manual for your hardware for more information.
For example, we know many worship keys players enjoy using the Korg nanoKontrol2. This device is class-compliant so it can be easily used within the Sunday Keys App.
Popular hardware MIDI controllers like the M-Audio Keystation and Hammer88 series, Arturia Keylab series, Studiologic SL series, and many more are all class-compliant.
Audio interfaces from popular brands like Focusrite, iConnectivity, Behringer, M-Audio, Radial, etc are class-compliant and can be used.
Again, if you’re not sure about your hardware check the user manual or manufacturer’s website to confirm.