Open the communication app or any application on your phone where the MIDI file is stored. Tap the file to open it, then tap the system’s built-in “Share” or “Open in another app” icon (usually a square with an upward arrow or a share link symbol).
In the share menu that appears, tap the “Muro Box” icon. Your phone will switch to the Muro Box app and display an import window. Confirm your song details, then tap “Save” to complete the import.