build a midi board

https://www.hackster.io/hackershack/midi-footswitch-b2e0b3

https://apps.apple.com/us/app/sidecar-midi-controller/id1073305840

https://github.com/alf45tar/PedalinoMini

https://gwerder.digital/products/Elektronik/Midi-Elektronik/midi-shield-fuer-alle-arduino-von-sparkfun.html

https://github.com/MicroMidi/NUX-MIDI-Footswitch

Bluetooth
https://www.electronicwings.com/esp32/esp32-bluetooth-getting-started

Arduino and HC-05 Bluetooth Module Complete Tutorial

Pi alternative

https://www.notebookcheck.com/Orange-Pi-5-Die-leistungssstarken-Alternativen-zum-Raspberry-Pi-gibt-es-ab-sofort-mit-riesigem-Arbeitsspeicher.760097.0.html