Animoog
Animoog is a well-regarded iOS synthesizer available in iPhone and iPad versions. Both versions use the identical audio engine but have slightly different user interfaces. On the iPad, you can run an instance of each app. The Anisotropic Synth Engine is a variety of wavetable synthesis that morphs between 8 timbres (wavetables)
App store description: Animoog, powered by the new Anisotropic Synth Engine (ASE), is Moog Music's first professional polyphonic synthesizer designed exclusively for the iPad. ASE allows you to move dynamically through an X/Y space of unique timbres to create a constantly evolving and expressive soundscape.
App type: App (IAA)
App store link: 
Developer: Moog Music Inc.
Developer AB Forum Handle:
Animoog Timbres
Animoog patches morph between 8 timbres (wavetables)
Moog Introduction to Animoog Timbres
See also
Animoog Timbre wiki page.
Guitar Moderne article in which Moodscaper developer Rob Jackson discusses creating custom timbres from fuzz guitar samples.
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