CamSextant allows measuring celestial objects altitudes with your phone
similar to a marine sextant. The app uses the phone sensors camera and GPS [optional].

Point the phone to a celestial object and capture the name altitude and time
for celestial navigation calculations.

You can calibrate the sextant index by reading the sea horizon altitude.

On screen celestial objects (Sun Moon 4 planets and 150 stars).
CamSextant has perpetual Nautical Almanac.

If set CamSextant speaks the celestial objects names and altitudes.

Best way to identify navigation stars and planets.

The program also calculates the Deltas for the each altitude reading
and the Astronomical Position (for two or more sights).

If you have a marine sextant at hand you can correct the phone readings with it and get some real celnav work done.

Nice for celestial navigation training even without a marine sextant.

For more information check:

CamSextant Tutorial