Just came across a very handy Celestial Navigation app for Android mobiles or tablets. All we need now is an electronic pair of binoculars for height measurements.
Would appreciate feed-back from boaters who have used it in practice.
The app is downloadable from Google Play at a small fee.
Having passed my celestial navigator exam 30 years ago I must say one should know how to use the sextant, sight reduction tables, nautical almanac and a bit of math before relying on electronic phone apps for any navigation. But I do admit having tried a few night sky apps to identify stars. and planets.