We believe celestial navigation is an amazing skill and develop Celestial Nav to offer a simple, yet powerful and all encompassing app for our users.
Celestial Nav is an easy to use, all-in-one tool which offers: • Celestial navigational computations for your device • Simple toolbar menu for quick access • Internally stored perpetual Almanac • Offline ready and functional without the need for other external tools • Quick and easy capture celestial observation data • High accuracy sight reductions • Star reference tables
SIGHT PLANNING • Local Hour Angle (LHA) for Aries • Star tables sorted by name, magnitude, declination, and SHA • Sunrise, sunset, twilight, and location reference • Moon phase reference
SIGHT REDUCTION • High accuracy sight reduction algorithm • Perpetual Almanac offering accurate data for years 1600 - 3000 • Almanac data for Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn • Detailed Almanac data for 58 navigational stars • Assumed Position (AP) for any user defined position • Line of Position (LOP) intercept data for accurate course and speed adjustments • Computational variables displayed for accuracy and validation
CELESTIAL FIX • Computations by USNO algorithm in the Nautical Almanac • Save all your LOP in an easy reference table
BASIC VERSION Free daytime celestial navigation tools using the sun: • Unlimited sextant sight reduction calculations • Sight reduction to a line of position using the sun • Perpetual almanac for the sun • Advanced sight corrections for index error, eye height, temperature, and pressure • Support for upper and lower limb reference • Star Table with navigational references • Detailed Sun references • Limited Moon references
PRO FEATURES (IN-APP PURCHASE) Advanced Day & Night Celestial Navigation includes all BASIC features plus: • Almanac data for 65 navigational bodies for years 1600 through 3000 • Map display for saved LOPs • View intercepts with course and speed corrections • Metric and imperial unit support with automatic conversions • Support for coordinate entries in different formats (H° M’ S” or Decimals) • Save all your LOP calculations for future reference • Save user preferences and settings • Unrestricted moon references • Almanac and algorithmic models for 65 navigational bodies: • Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn • 58 navigational stars
REFERENCES Sight reductions and celestial calculations use various internationally accepted references for the most accurate results: • Jean Meeus - Astronomical Algorithms • US Naval Observatory (USNO) Almanac and Algorithms • Hipparcos New Astrometric Catalog, Published 2007 • ELP2000-85
SUBSCRIPTION TERMS Celestial Nav is free to download and the basic features free to use. A paid upgrade to the PRO version provides access to premium features and additional tools. We may offer trial subscriptions that give limited time access to all PRO features and premium content for the duration of the trial period. Trial subscriptions automatically expire and the app will revert back to the Basic version thereafter. No data is lost but access and use of premium features will no longer be available.
Celestial Nav 3.4 Update
2025-12-27
Thanks to user feedback, we fixed the localization issues experienced in some countries with the input and display of decimals and various number formatting.
AppPure.com and the download link of this app are 100% safe. The download link of this app will be redirected to the official App Store site, thus the app is original and has not been modified in any way.
Thanks to user feedback, we fixed the localization issues experienced in some countries with the input and display of decimals and various number formatting.
3.3
2025-09-12
CelestialNav is ready for iOS 26.
This release includes various behind the scene tweaks: - Improved result accuracy by a few more decimals for various celestial calculations and variables
3.2.3
2025-05-14
We fixed a user reported bug that displayed incorrect sunrise/sunset times when local noon falls on a different date.
3.2.2
2025-02-12
Bugfix: Crash after alert display on iOS18+
Tooltips and help features continue to be expanded. Various titles and labels display definitions and further guidance when tapped.
3.2.1
2025-01-26
This update includes further improvements and iOS 18 support behind the scenes. Improved purchase restore functionality added.
Tooltips and help features continue to be expanded. Various titles and labels display definitions and further guidance when tapped.
3.2
2024-09-21
iOS 18 support with a logo upgrade and full dark mode support.
Tooltips and help features continue to be expanded. Various titles and labels display definitions and further guidance when tapped.
3.1.5
2024-06-20
Version 3 of Celestial Nav brings a NEW Noon Sight feature to calculate latitude and longitude. The PRO version has advanced noon sight methods such as plotting a noon curve with multiple sights to determine the most accurate zenith of the sun and improve overall accuracy.
Tooltips and help features continue to be expanded. Various titles and labels display definitions and further guidance when tapped.
Bug fixes: - improved Upgrade experience - fix crash caused by multiple fast tabs on the same menu
3.1.4
2024-05-28
We squashed a few bugs
3.0.1
2024-03-17
Version 3 of Celestial Nav brings a NEW Noon Sight feature to calculate latitude and longitude.
The PRO version has advanced noon sight methods such as plotting a noon curve with multiple sights to determine the most accurate zenith of the sun and improve overall accuracy.
Tooltips and help features continue to be expanded. Various titles and labels display definitions and further guidance when tapped.
New: - Noon Sight - Mean Noon Sight: Use two readings at equal height before and after zenith (PRO Only) - Noon Curve: Polynomial regression for multiple sun readings to calculate more accurate zenith time and position (PRO Only)
Bugfixes: - bug fix to resolve startup crash in Dark Mode for certain devices - major bug fix to resolve crash on iPad when an alert should be presented - fixed several layout issues - improve support for all iOS screen sizes
2.1.2
2023-09-03
We made some behind the scene performance updates and fixed layout issues.
Based on valuable user feedback improvements were made to the Map Display for saved LOPs (PRO Feature). Markers can now display the AP and plotting lines for each LOP. When tapped, additional details are shown directly on the map.
In addition, a tooltip feature has been launched so various titles and labels display a definition and further guidance when tapped.
New: - MAP annotations to show LOP details when tapped - Unknown body identification - Tooltips
Bugfix: - fixed centering of the map based on first shown LOP
2.1.1
2023-07-24
Based on valuable user feedback we have improved the Map Display for saved LOPs (PRO Feature). Markers can now display the AP and plotting lines for each LOP. When tapped, additional details are shown directly on the map.
A tooltip feature has also been launched so various titles and labels display a definition and further guidance when touched.
New: - MAP annotations to show LOP details when tapped - Unknown body identification - Tooltips
Bugfix: - fixed centering of the map based on first shown LOP
2.0
2023-05-30
We have been working hard to improve the overall app experience and return the most accurate results. Based on user feedback, we added a new feature to identify a celestial body based on a bearing and height reading. A tooltip feature has also been launched so various titles and labels pop out a definition and further guidance when touched.
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New: - Unknown body identification - Tooltips
Updates: - accuracy tweak for stars algorithm
1.4.10
2023-05-09
New: - Added tooltip help information. Click a title, label, or header for additional information where available.
Updates: - subscription status improvements
Bug Fix: - fixed an almanac bug for Jupiter calculations - fixed a sync issue verifying PRO version status
1.4.7
2023-04-18
Bug Fixes: - fix crash when changing settings - Time layout errors for Moon and Sun data
Updates: - process and performance optimizations for iOS 16+ - layout improvements
1.4.6
2023-02-13
Updates: - process and performance optimizations
1.4.3
2022-10-01
Now offering lower cost subscriptions.
New PRO Features: - Enhanced visual map for saved LOPs - Enhanced course and speed corrections
Updates: - Background process improvements
1.4.2
2022-09-25
Now offering lower cost subscriptions.
New PRO Features: - Enhanced visual map for saved LOPs - Enhanced course and speed corrections
Updates: - Improved layout on iPad and large screens
1.4.1
2021-11-02
Fix PRO Upgrade issues
1.3
2021-11-02
New PRO Feature: - Visual representation and map display of saved Line of Positions
Updates: - Fix issue with current position formatting - Add Dip information - Behind the scenes improvements
1.2.1
2021-11-02
Minor bug fixes
1.2
2021-11-02
New Features: - Sun information tab with sunrise, sunset, twilight and more - Moon information tab with phase details - Added localization (GPS) support for quick position entry
Changes: - Behind the scenes improvements - Layout adjustments for better user experience