Touch OSC is Modular Open Sound Control and MIDI for iPad/iPhone/iPod Touch, as well as Android based touch screen hardware. Here's a template to control the Evolver from TouchOSC:
This template was not created by DSI, and we make no warranties or claims to its effectiveness, correctness, use, or abilities. That being said, enjoy!
The Template is available as an attachment directly at the bottom of this post.
Original file download link: http://www.edisk.cz/stahni/41495/evolver_touchosc_template_autumnist.zip_290.53KB.html
Created by The Autumnist: www.autumnist.com
More info on TouchOSC: http://hexler.net/