vWave-Lite allows you to control Color as distributed in Final Cut Studio.
The three "virtual" trackerballs allow you to control the colour differential and masters in the Primary In, Secondaries and Primary Out rooms in Color.
It's great that these FCP friendly apps are being made for the iPad, even better is that it's free. Check it out on the Tangent website here
You can also download it from iTunes.
Walter Biscardi also comments on using the app in his Creative Cow blog.