The note grid is organized with time progressing vertically from top to bottom in 16 steps or lines (0 to 15), marked on the left. The current line being played is indicated by the highlighted cursor. The notes are arranged horizontally with lower notes on the left and higher notes on the right. Octaves are indicated by outlined grid positions. The octave size and note range are selected in the instrument summary for each instrument. Each block pattern contains a sequence of note on and note off events. Note events are indicated by a filled note position (play a note) or a horizontal line (stop any note previously played at that tone). When edit mode is enabled, notes are added by tapping a note position and removed by tapping the same position again. The note is also played and can be heard in realtime, regardless of the edit mode.
Each instrument has a different color and the notes of the current instrument are shown more brightly than the notes of other instruments, which are still visible for reference.