Borderlands Granular
Borderlands Granular is a granular synthesis app with an innovative touch interface. Considered by many to be an essential sound design and sound exploration tool.
App type: App
App store link: 
Developer: Chris Carlson
Audiobus Support: Yes
Additional Info
From the developer's web site:
Explore, touch, and transform sound with this unique interface for granular synthesis, a technique that involves the superposition of small fragments of sound, or grains, to create complex, evolving timbres and textures.
Borderlands emphasizes gestural interaction over knobs and sliders. Create, drag, and throw pulsing collections of grains over a landscape of audio files, or use the built-in accelerometer to sculpt sound with gravity.
Other Articles of Interest
Ambient guitar techniques: Borderland Granular + ToneStack + Animoog
Videos
Tutorial (by Chris Carlson)
Borderlands 2 New Features In Use (sound demo - some titles - no speaking)
Borderlands Granular in Use (Chris Carlson)
Haq Attack Tutorial (1 hour 50 minutes)
Rich Ambient Pads from Fuzz Guitar by Moodscaper (ToneStack+Borderlands Granular)
Borderlands / Animoog Composition by Moodscaper
More Borderlands + Animoog from Moodscaper
Cloud Guitar 2.0 from Moodscaper (ToneStack+Animoog+Borderlands Granular)
More videos from Chris Carlson on his Vimeo site.
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