PEOPLE living in Shanghai will soon be able to check the level of construction dust in the air via a smartphone app, an official said yesterday. The new service will be developed as part of a program to install dust monitors across the city, said Zhang Chaoyun, deputy director of the Shanghai Environmental Sanitation Management Office. "Data from the sensors will be analyzed and the results sent to district sanitation authorities, which can then take action, such as spraying water to damp down the dust," he said.