MIDI keyboard – using a real instrument with iPad - TapSmart
USB MIDI Keyboard Controller 25-Key as Gift for Son,Donner N-25 Portable MIDI Keyboard with Velocity-Sensitive Keys & Light-up Rocker for iPhone, iPad, Mac and PC. - Walmart.com
MidiPad 2 - The Ultimate Midi Pad Controller For iOS
Best MIDI keyboards for your recording rig | 2021 Edition - 9to5Mac
Finale Blog: Using your iPad as a MIDI Controller - Finale
Connecting iPad as a MIDI controller for Logic Pro (or GarageBand) on Mac OS using a charger cable - YouTube