# iSextant

> Sun sight reduction program for location confirmation and astro-navigation learning. (iPhone/iPad app by HydrogenSC Ltd.)

- Source: https://appshunter.io/ios/app/isextant/id362351673 (this page in markdown: same URL + `.md`)
- Developer: [HydrogenSC Ltd](https://appshunter.io/developer/362351676)
- Category: Navigation, Travel
- Price: $2.99
- Rating: 5.00/5 from 1 App Store ratings · 1 written reviews indexed
- Age rating: 4+
- Requires: iOS 7.0 · 1 MB
- Languages: English
- Released: 2010-03-19
- Data updated: 2026-06-10
- Monetization: paid
- User reviews in markdown: https://appshunter.io/ios/app/isextant/id362351673/reviews.md

## What is iSextant?

iSextant is a sun sign reduction program, that can be used to confirm your location in the event of GPS signal problems.

It is important to note that in increasing world orbital use/misuse we are always closer to the http://en.wikipedia.org/wiki/Kessler_syndrome where there is an increasing chance of GPS outage.

iSextant can also be used as an aid to learning astro-navigation.

It requires that you take a sun sight using a Sextant and note various other conditions, such as pressure and temperature. Using this information along with an assumed position the program with give you GHA, Declination of the Sun followed by an Azimuth and Intercept from your assumed position.

For more information about astro-navigation please refer to http://en.wikipedia.org/wiki/Astro_navigation.

## Key features

- Sun sign reduction for location confirmation
- GPS signal backup
- Astro-navigation learning aid
- Calculates GHA, Declination, Azimuth, and Intercept
- Requires manual sun sight input

## Recent user reviews (1 of 1)

All indexed reviews: https://appshunter.io/ios/app/isextant/id362351673/reviews.md

### 5/5 — Fantastic and easy

*2013-09-01*

Very easy to use. All you need is a sextant. Input a few simple items and you have your lop. If you make a mistake such as entering local rather than gmt the answer is so wrong you'll know you made a mistake. I have 4 GPS on board so I don't worry much about the fact I don't carry tables so if the world ends I will be lost.

## Frequently asked questions about iSextant

### What is iSextant used for?

iSextant is a sun sign reduction program used to confirm your location, especially when GPS signals are problematic. It also functions as a tool for learning astro-navigation.

### How does iSextant work?

You take a sun sight with a sextant and input conditions like pressure and temperature. iSextant then uses this data with an assumed position to calculate GHA, Declination, Azimuth, and Intercept.

### Is iSextant useful for learning astro-navigation?

Yes, the description explicitly states that iSextant can be used as an aid to learning astro-navigation, providing calculations like GHA and Declination.

### What information do I need to use iSextant?

You need to take a sun sight using a sextant and note other conditions such as pressure and temperature. An assumed position is also required for calculations.

### Does iSextant require an internet connection?

The description does not specify internet requirements for core functionality, but it is designed to work when GPS signals are problematic, suggesting offline utility for its primary calculations.

### What devices support iSextant?

iSextant is supported on iPhone, iPad, and iPod devices.

### How often is iSextant updated?

The latest version, 4.0, was released on June 2, 2015. The app has not received updates since then.

### What is the age rating for iSextant?

iSextant has an age rating of 4+.

## Version history (last 5 releases)

### 4.0 — 2015-06-02

This app has been updated by Apple to display the Apple Watch app icon.

Upgraded to IOS 7+ UI and to 64bit architecture.

### 2.3 — 2012-03-18

Fixed height of eye error and GHA bugs.

### 2.2 — 2012-01-23

The index error is no longer expressed in minutes of a degree, but in whole degrees same as the height measurement itself, and thus more consistent.

### 2.1 — 2011-01-12

Directional bug rechecked and fixed.

### 2.0 — 2011-01-08

Summary page has more information on it.

Assumed position direction bug fixed.

## More apps by HydrogenSC Ltd

- [Kryptofolio+tax](https://appshunter.io/ios/app/kryptofolio-plus-tax/id921388783)

All apps by HydrogenSC Ltd: https://appshunter.io/developer/362351676

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-10.*