Shiny is used here to add interactivity to my ambulanceR package. Leaflet enables us to build the control widget directly on map. Working on maps, it’s great to add a widget to allow users to switch between different months, using one layer or another. It is possible to differenciate the ambulance incidents on the map so that selecting color maps provide a particular information. When the user select the incident range on the “slide bar” button, the leaflet map automatically displays to the user’s option.