It is possible to insert a waypoint by pressing on the magenta vector (leg) and dragging it to a waypoint on the map. As a result a new waypoint will be inserted in the «Route». If the location on the map is not over an existing waypoint, a «temporary» waypoint will be created. You can add this waypoint later to the database if you wish to do so. You can also do this by tapping on a waypoint of the route and dragging it to a new location.