Midiflow allows you to send MIDI from app to app in a similar way to what you already do with audio. That way, you can sync apps with each other or send MIDI parts from a sequencer app to different synth apps. You can also route the MIDI from your keyboard to apps and assign different key zones to them. Different settings can be stored as a preset, recalled later and inserted into another preset. Furthermore, all MIDI transfer can be monitored in order to find problems or just to learn what MIDI is doing (normally) behind the scenes.
Download Midiflow on the Apple App Store
Learn more on midiflow.com