Lets you strum chords on a synthesizer using a smartphone or computer and mouse
Download the harp.html file and open it in your browser, or visit https://www.floydsteinberg.com/extension/www.floydsteinberg.com/webmidi/harp.html
Give it access to your MIDI and Microphone (the latter is for synths that register as audio devices)
Connect your synth to your phone or computer via USB or MIDI interface
Turn off local mode if only one synth is used
Select the MIDI input and output in the top right corner
If your synth doesn't appear there, reload and try again
Play a chord on the keyboard
Strum on your smartphone or computer using the mouse