Getting Started with the CelNav 360 app (Android version)
Celestial navigation exploits the principle that every measurement taken with a sextant converts to a line of position on a chart, the intersections of two or more such lines providing a position fix.
1 - Set Assumed Position
Tap AP in the action bar
2 - Sight Preparation
Tap MODE in the action bar to toggle a view of the computed horizon at the assumed position
3 - Add a Sight
Open the Sights Table by tapping the icon at the bottom right of the screen.
Tap the sextant icon and select from Sun/Star/Planet/Moon
The dip correction at the bottom left of the dialog may be adjusted by tapping on it
4 - Lines of Position
The line of position derived from each sight is represented in the table by its intercept and azimuth.
Tap MODE in the action bar to toggle a graphical view of all the lines of position in the table
5 - Sight Reduction Detail
Select a table entry and tap altitude
6 - Bibliography
A standard reference work for sight reduction and other techniques of celestial navigation is
Bowditch's American Practical Navigator
https://msi.nga.mil/Publications/APN