In effect making Caustic as useful for FL Studio for PC as the official app from Imageline.
The only advantage in my opinion that FL Studio Mobile have over Caustic is if you want to record things live directly in the app as the piano keyboard is velocity sensitive as is the Drum pads ( which will soon be the same in Caustic ). Making it easier to get a variety of velocities without having to program it in. And yes the keyboard is much better in general in FL Studio. ( Recording with latency... remember to do the recordings on any app with too much latency in slower tempo and the latency will be better when you speed the tempo up later. )