Step 4: more options

MIDI Monitor

You can monitor the MIDI traffic quite easily with Snoize MIDI Monitor. You can see the channel, the notes On and Off and the velocity.

GarageBand

You can use your brand new MIDI controller with the famous app.

1. Make sure the MIDI controller has been detected. Go to Preferences > Audio/MIDI. Here you should see 1 MIDI input(s) detected

2. Create a new project > Keyboard collection

3. Select a keyboard and start playing