Rhythm necklaces are circular representations of repeating patterns. They’ve found application in fields as varied as Crystallography, Radio Astronomy, Nuclear Physics, and Ethnomusicology. When applied to musical rhythms, circular representations show the underlying geometric properties that make them enjoyable, such as the degrees of evenness and symmetry. Computer scientist Godfried Toussaint has found that analyzing rhythms geometrically reveals surprising relationships between rhythms the world over. In fact, Toussaint has shown how a core group of geometric algorithms can generate rhythms employed in African, Cuban, Balkan, and Spanish folk music, to name a few. The Rhythm Necklace iOS app is a musical sequencer for exploring the geometry of rhythm necklaces, and for experimenting with generating rhythms algorithmically.