Mature synth, lots of features; three voices; works great! – Crystal Synth Review

Musicians take note: Crystal has been a mainstay of the VST synth world for several years, and it has been regularly updated as time goes by. On the iPad it is a stand-alone synth (not a plugin) has a broad range of features: modulation matrix, six LFOs, three voices (each with its own filter and amplitude envelope). This iPad version makes good use of finger gestures, for example, on the envelope drawing pictures. It comes pre-loaded with quite a few patches. A fun feature is the "Breed" button which generates a random patch.
Review by SF musician on Crystal Synth.