Five popular sailing apps are reviewed: 1) Imray Marine Rules and Signals is a reference tool for boat rules, signals, and communications at sea. 2) Navionics Boating provides navigational charts that can be downloaded, and allows tracking routes and sharing location with others. It has additional upgrades available. 3) WeatherPro gives weather forecasts including temperature, wind, and probability of rain. It has alerts for extreme weather. 4) PredictWind provides high-resolution wind forecasts and maps with departure planning and route optimization based on wind conditions. 5) Compass Eye overlays a compass on live camera views for navigation on land or water, and provides bearings, speed, and course readings with