What can you connect to the new iPad Pro with USB-C? - 9to5Mac
iRig Keys I/O is an audio interface and MIDI keyboard controller for $199
12 Best MIDI Controllers Which Are 'Actually' Worth Buying - Audio Mentor
Amazon.com: USB-C Printer Cable,Type-C to Type-B Cable Compatible with iPad Pro(with USB-C Port)/MacBook/iMac/Mac Mini/Mac Pro,PC,Laptop,Smartphone and Orther Devices with USB C Port. : Musical Instruments
How to find the best MIDI Keyboard Controller - gearnews.com
Nektar Technology Impact LX25+ USB MIDI Controller IMPACT LX25+
Amazon.com: Xkey 25 USB MIDI keyboard controller - Apple-style ultra-thin aluminum frame, 25 full-size velocity-sensitive keys, polyphonic aftertouch, plug & play on iPad, iPhone, Mac, PC : Everything Else
Connecting midi usb keyboard piano into Ipad Pro and playing for Live Sound - YouTube
Stage Right by Monoprice SRK Mini Portable 25-key USB MIDI Keyboard Controller with 8x RGB Velocity Sensitive Pads and USB Power - Monoprice.com
Is Apple iPad Pro 2018 Good For Musicians Without A Headphone Output?
Akai Professional LPK25 Wireless | 25 Mini-Key Bluetooth MIDI Keyboard