With 1.7 update Cubasis brings support of Inter-App Audio.
IAA implementation in Cubasis is powerful yet easy to use.
You can have IAA-compatible apps as sound source for Audio Tracks in Cubasis, Instrument on MIDI tracks (yes, you don’t need to tracks anymore, it can work with IAA synths/samplers like with VSTs on desktop, one single midi track) and Insert/Send effects.
IAA apps as MIDI instruments are implemented very well. You choose the IAA instrument and just start playing without switching to the app (it opens in the background). When you’ve composed midi it can be easily bounced (with all the effects you’ve applied to the track as well) by freezing the track new audio track with bounced data will be created.