During Skyrise we developed an iPad (and iPhone) companion system for the VEX Cortex. It served as an aid during programming and debugging robot code and subsystems.
Our original intent was to control our robots with the iPad, but that idea evolved into creating something more useful.
We are currently working on UI and making it able to control the robot.
Here is our document we created for our engineering notebook: https://docs.google.com/document/d/1Af40XJ-CnHQVF2C38oCycmWOmKjSlISQiBXxaaR16i4/edit?usp=sharing