Regarding a control surface, this is the formation I settled on using the ipad. The controls I use most are the XY pads for wave shaping and the switches for the FM and frequency mode. I like the idea of it being multitimbral (midi channel buttons are up top + 'send all,' top right) but without a way to save presets it doesn't make sense yet. To me these are the controls that make the Goom unique. Freq mode>KEY and FM>MIX gets you decent bread and butter synth sounds. Flicking it to freq mode>HI and FM>FM+FB gets you instant grainy, delay like wierdness to full on wall-of-digital-filth, depending on the XY pad positions. As I mostly use an external analog filter with it (X-pole or stereo shruthi) I hardly use the filter / filter EG.