Alexander Zolotov has released v1.3 of PixelWave and v1.1 of SpectrumGen. The updates add MIDI in support.
PixelWave is an experimental synth for the iPad, iPhone & iPod Touch with old school pixel interface featuring a multitouch arpeggiator and the ability to draw waveforms and play them at the same time.
SpectrumGen is a spectral synthesizer with simple and effective user interface. SpectrumGen is similar to PixelWave, but instead of drawing the waveform you draw the spectrum of sound!