The iPad edition of Sinevibes Sequential 2 is a step-sequencing effects processor, with 11 lanes hosting a range of devices - bitcrusher, frequency shifter, flanger, phase oscillator, filters and more.
"Up to 60 seconds of real-time manipulation can be recorded to WAV"
Simply load an audio file (from the bundled library or imported) then activate one step per beat division (1/8 to 1/32) to send it through the effect on that step's lane.
Each effect has one adjustable parameter (frequency shift, filter cutoff, etc), and up to 60 seconds of real-time manipulation can be recorded to WAV.
The touchscreen interface suits Sequential particularly well (except for the fiddly playback parameters at the top), and it sounds every bit as mad, bad and awesome as its OS X counterpart... but with AudioCopy/Paste being its only connection to the outside world, it's another one that desperately needs IAA/AudioBus added before it can get our full recommendation.