Controls Touch gestures supported: Single tap: If panning is enabled, follow the tapped particle. Otherwise, create a new particle. Double tap: Put camera focus on a particle. Pinch: Zoom the view. Panning / Dragging: If panning is enabled, it will pan the view. Otherwise, it will create a particle with momentum. Option bar: Small, Medium, Large buttons: Choose a particle size. Pan / Follow button: Toggle between panning/following or sling-shotting particles. Settings menu (cog icon): Pause: Toggle pause. Particle trails: Show / don't show. Collision mode: Bounce / merge particles. Reset zoom: Resets the zoom to default. Reset particles: Removes all the particles from the field.