DragonSF has created a Web GUI for Teensy 4.1 with a focus on audio projects. The system consists of a Node server (with some HTML/JS/CSS magic) and a Teensy library, which communicate via Ethernet to allow interactions with the GUI to affect firmware on the Teensy board.

As such, the project requires the Ethernet Kit for Teensy 4.1, as well as 8MB PSRAM and our USB Host Cable for MIDI. The web server and library code can be found on GitHub, and an example implementation, TMSidekick2, is also available on GitHub, including source code and schematics.