The Modular V2 Controller is a MIDI controller for the iPad to wirelessly control the Arturia Moog modular V2 virtual instrument.
On the VST side, the wireless MIDI is enabled with:
You can download rptMIDI from here.
To start using the app, the Arturia Moog Modular application needs to learn all MIDI controller messages. This can be done by enabling the MIDI learn option. Then, after selecting a knob in de Moog Modular it will recognize the incoming messages. Note, these messages are all NRPN messages.