The messages that are sent from the Motion Synth App to an audio app (or external software/hardware) to modulate sound are called MIDI messages.
MIDI is the most widely supported method for communicating realtime musical information, and all modern DAW (digital audio workstation) software supports MIDI.
Many Audio apps allow extensive expressive control of their sounds via MIDI.
MIDI Mapping refers to an automated way of setting up control of specific parameters in software.
For some introductions to MIDI please visit:
The most common type of MIDI message that is used to control sound parameters is called a 'Continuous Controller' message (or 'CC' message for short), and the Motion Synth App sends these messages via any 'Send Continuous Controller (CC) MIDI messages' module that is added or removed from the Motion Tab.
Each CC message has a 'MIDI Controller Number' which determines the parameter that will be changed by the message.
To control the sound of your chosen audio app, you need to know which MIDI Controller Numbers it responds to. Please refer to the developer of your chosen audio app to learn about which MIDI Controller Numbers they use to receive CC MIDI messages.
For the majority of use cases, you can ignore MIDI Channel Number and leave it set to the default value of 1. This is because many MIDI recipients receive messages on all channels by default. One possible reason for changing MIDI Channel Number might be to send different MIDI messages simultaneously to different recipients.
If an audio app responds to MIDI CC messages at all, it will most likely give some kind of response to CC messages to MIDI Controller Number 1 (the Controller number associated with the 'mod wheel' on a MIDI keyboard).
Thus, if you are working with a new synth, a good place to start is to add a Send CC module to the Motion tab and set its MIDI Controller number to 1.
Responsiveness to 'pitchbend' MIDI messages is also common. Try adding a Pitch Bend module in the Motion tab of the Motion Synth App to experiment with this.