PolyRhythmApp is a musical app that helps you study and practice various polyrhythms in a wide range of time signatures, tempos and harmonic environments. The app loops through a number of bars (between 1 to 16) and in those bars it plays the pulse (quarter notes), the chosen subdivision of each beat (the subdivision can be set to 2, 3, 4, 5, 6 or 7 parts per beat), can emphasize the first beat (of each bar or of the whole segment), bass notes (that can be defined rhythmically for each subdivision position) and the selected polyrhythm. Each sound layer can be turned on or muted independently while the pulse is still playing. The volume can be adjusted to suit the output device. Each specific setting can be saved with a chosen name and loaded. PolyRhythmApp provides an invaluable practice tool for both the professional musician and for the student, is easy to learn and easy to use.