EPAs Cyanobacteria Assessment Network Application (CyAN) is a mobile app that provides users weekly satellite data to identify the concentration, location, and time series of cyanobacterial blooms in fresh and coastal waters of the United States. It is designed to inform decisions regarding recreational and drinking water safety by providing water quality managers with a user-friendly platform that reduces the complexities associated with accessing satellite data to allow fast and efficient initial assessments across water bodies. EPA scientists developed the CyAN app to help support local and state water quality managers make faster and better-informed management decisions during blooms.