I can see the use of iPad as a remote for lot of things in Cubase 6. For example, as remote for the VST Effect Editor - VST Editor. As for mixers and so on...
Apple - iMac 27" 3.2 GHz Intel Core i5 - 8GB Ram - OSX 10.8.3
HP - Pavilion dv6-3315sp Core i5-480M - 8GB Ram - Windows 7
PreSonus AudioBox 22VSL Audio Interface
Steinberg - Cubase 7.0.4
Steinberg - WaveLab 8
Avid - Pro Tools 9
Apple - Final Cut Pro X