If anyone would like to know more before clicking over, here is some text quoted from the linked site:
Features of the app include: state boating information; a safety equipment checklist; free boating safety check requests; navigation rules; float plans; and calling features to report pollution or suspicious activity. When location services are enabled, users can receive the latest weather reports from the closest National Oceanic and Atmospheric Administration weather buoys as well as report the location of a hazard on the water.
The app also features an Emergency Assistance button which, with locations services enabled, will call the closest Coast Guard command center.
The app is self-contained, so personal information is stored on the phone and is not sent to the Coast Guard unless the user chooses to send it. The Coast Guard does not track a user’s location, and the app does not track a user’s location unless the app is being used.