Nautical Calculator, developed by Binary Solutions, is a free Android application that provides a comprehensive set of tools for sailors and navigators. This app offers calculators for celestial navigation, conversions, distance, log and trig, sailings, time zone table, and weather data.

The celestial navigation calculator includes altitude correction for air temperature, atmospheric pressure, and altitude factors, among others. The conversion calculator provides chart scales and conversion for nautical and statute miles, as well as meters, feet, and fathoms. The distance calculator offers various methods to determine distances, including dip of sea short of the horizon, distance of an object by two bearings, and geographic range.

In addition, the app includes log and trig functions, calculations for great circle and Mercator sailings, and a time zone table. The weather data calculator provides barometer measurement conversions, correction of barometer reading for gravity, and direction and speed of true wind, among others.

Overall, Nautical Calculator is an excellent tool for sailors and navigators who need quick access to a wide range of calculations. The app is easy to use and provides accurate results. However, it would be helpful if the app included a tutorial or user guide to explain some of the more complex calculations.