Narwal Robot Vacuum and Mop A relative newcomer to the robotic vacuum market, Narwal offers a sweeping and mopping combination that's impressive. However, it's expensive and hampered by a cumbersome app with a steep curve. To mop, you drop a sheet of detergent into the base station's clean water tank. https://robotvacuumcleaner40913.tinyblogging.com/how-you-can-use-a-weekly-best-rated-robot-vacuum-project-can-change-your-life-71496379