Control the Behringer 2600 in your browser over WebUSB / WebMIDI - edit device settings, run the step sequencer, record MIDI and check firmware, no install or drivers. Functions: General, Calibration, Update. Also known as 2600 Blue Marvin, 2600 Gray Meanie.
Official app: SynthTribe. Connection: WebUSB discovery + WebMIDI SysEx.
Variants: 2600 Blue Marvin, 2600 Gray Meanie.