SightGeist is a simple, offline tool for traditional celestial navigation. It runs entirely on your device—no internet connection or data sharing required.

It offers sight reductions of sun, moon, the traditional navigational stars and planets.

Simply enter assumed latitude/longitude, date/time, observed altitude (plus index error and eye height), then choose the body you’ve sighted. SightGeist returns the declination, GHA, calculated/true altitude, intercept and bearing. It also features a sky plotter for precomputing sights.

Ideal for students, navigators and amateurs who want to explore celestial sight-reductions without online services or ad networks. If you enjoy understanding each stage of the computation, this app keeps everything on-device.