MIDI In/Out settings in Logic Pro for iPad
Bluetooth MIDI Devices
Tap Bluetooth MIDI Devices to open a dialog for setting up your external Bluetooth MIDI controllers to use with Logic Pro. There are two pages for settings, Connect and Advertise:
Connect: Use the Connect settings to configure your external Bluetooth MIDI controllers to send and receive MIDI signals to and from Logic Pro. Each device is listed along with its status, for which there are three options:
Not Connected: Logic Pro receives a pairing signal from the device, and you can tap Not Connected to connect the device.
Connected: The device is currently connected (paired), and you can tap Connected to disconnect it.
Offline: This is a previously connected device that is currently not available. Once a pairing signal is detected, the status changes to Not Connected.
Advertise: Use the Advertise settings to configure how Logic Pro is recognized by other Bluetooth devices.
Name field: The name of your iPad is displayed by default, but you can tap the field and enter a different name that other Bluetooth devices will see.
Advertise MIDI Service switch: Turn Advertise on or off to have your iPad be discoverable by other MIDI Bluetooth devices.
MIDI Input Devices and Ports
Any MIDI device that can send MIDI messages and is recognized by Logic Pro is listed under MIDI Input Devices and Ports with a switch to activate the device as a MIDI source. Only devices that are activated are displayed in the MIDI Input pop-up menu in the Track inspector.
Note: You can choose a MIDI device as a destination in the Track inspector MIDI Output pop-up menu even if it’s not activated as a MIDI source.
Various types of MIDI devices are recognized in Logic Pro:
Network Session 1: This option represents the network connection you create in the Audio MIDI Setup app on a Mac to send MIDI between Logic Pro for Mac and Logic Pro for iPad.
Logic Pro Virtual In: Receive MIDI data from any app on your iPad that supports this virtual MIDI bus, such as GarageBand for iPad. Third-party iPad music apps might display this option as a selectable MIDI output.
Internal app: Most iPad music apps that can send MIDI data internally between apps are listed automatically when you open them on your iPad.
Bluetooth connection: Any Bluetooth MIDI device needs to be added manually in Logic Pro in the Bluetooth MIDI Devices dialog.
Physical connection: A MIDI device that is Core MIDI compliant is automatically displayed in the MIDI Input Devices and Ports list if you connect it to the iPad’s Lightning or USB-C port.
The MIDI Input pop-up menu in the Track inspector lets you choose which MIDI device to use as the input for an individual software instrument track. See Record multiple MIDI devices to multiple tracks.
Note: The Play Surface option is always available in the MIDI Input pop-up menu. To connect and disconnect Bluetooth devices, tap Bluetooth MIDI Devices to open the Bluetooth MIDI Devices dialog.
Add Bluetooth MIDI devices
In Logic Pro for iPad, tap the More button
on the right side of the control bar, then tap Settings 
.Tap App Settings, tap MIDI on the left, tap In/Out, and then tap Bluetooth MIDI Devices to open the Bluetooth MIDI Devices dialog.
Tip: You can also tap the MIDI Input pop-up menu in the Track inspector of a MIDI track and choose Bluetooth MIDI Devices to open the dialog.
Tap Connect at the top (if it’s not already selected), then tap a row with the status Not Connected, indicating a device ready to be connected.
The status next to the device name changes to Connected; tap Connected when you want to disconnect the device.
Tap Done or swipe down to return to the MIDI In/Out settings.
The MIDI In/Out settings now lists the connected devices.
Remove offline Bluetooth MIDI devices
You can remove any previously connected device (marked as Offline) from the list.
In Logic Pro for iPad, tap the More button
on the right side of the control bar, then tap Settings .Tap App Settings, tap MIDI on the left, tap In/Out, and then tap Bluetooth MIDI Devices to show that dialog.
Tap Connect at the top (if it’s not already selected), then do either of the following:
Swipe left on an offline device, then tap the red Forget button that appears.
Swipe all the way to the left on an offline device to remove it immediately.
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