# Perpetual Nautical Almanac > Real-time celestial body positions and navigation data for maritime use. (iPhone/iPad app by RPA Technologies.) - Source: https://appshunter.io/ios/app/perpetual-nautical-almanac/id1483007345 (this page in markdown: same URL + `.md`) - Developer: [RPA Technologies](https://appshunter.io/developer/1317678667) - Category: Navigation - Price: $6.99 - Rating: 5.00/5 from 1 App Store ratings · 8 written reviews indexed - Age rating: 4+ - Requires: iOS 17.6 · 123 MB - Languages: American English - Released: 2019-10-10 - Data updated: 2026-08-29 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/perpetual-nautical-almanac/id1483007345/reviews.md ## What is Perpetual Nautical Almanac? Using the U.S. Naval Observatory NOVAS library and solar system ephemerides from JPL, high precision positions can be calculated in real-time from 1900 to 2050. Simply select date and time and all values are recalculated instantly. The estimated elevation value is only needed for calculating sunrise/sunset, twilight, and moonrise/moonset. The app provides the following functionalities: *Aries: GHA position *Sun: -GHA/dec - Astronomical dawn, nautical dawn, civil dawn, sunrise, sunset, civil dusk, nautical dusk, astronomical dusk, and meridian passage at Greenwich. - Semidiameter - Sunlight world map with the Sun and the Moon position. *Moon: - GHA/dec - Moonrise/moonset and meridian passage at Greenwich. - Semidiameter - Moon phase and age of the Moon. *Planets: - GHA/dec for Venus, Mars, Jupiter, and Saturn. *Stars: - Magnitude, SHA/dec of 99 stars ordered by SHA. *Corrections: - Correction for the atmospheric refraction. - Correction for the dip of the horizon. - Parallax correction for the Moon, the Sun, Venus, and Mars. ## Key features - Real-time celestial body positions - Sunrise/sunset and moonrise/moonset calculations - Sunlight world map with celestial positions - Moon phase and age - Planet and star GHA/dec - Atmospheric refraction and dip corrections ## Recent user reviews (8 of 8) All indexed reviews: https://appshunter.io/ios/app/perpetual-nautical-almanac/id1483007345/reviews.md ### 5/5 — V2 Update *2024-10-12* Excellent upgrade. Very easy to understand with some great new features. I highly recommend this app. **Developer response:** Please update to version 2.0 with a completely redesigned interface, with several screens that facilitate the use and visualization of data. Added precision and funcionalities. ### 5/5 — Latest Update - Big Improvement *2024-10-01* Replaces the need for your physical almanac. Gives you all the data you need to calculate your LOP. ### 1/5 — Readability Poor *2023-12-22* The app only lacks a more readable user display. The llight characters on a light background are very hard to read. **Developer response:** Please update to version 2.0 with a completely redesigned interface, with several screens that facilitate the use and visualization of data. Added precision and funcionalities. ### 1/5 — Doesn’t work. iOS 16.1 *2022-11-08* Doesn’t work. iOS 16.1 **Developer response:** We have just released version 1.3.5 which fixes the problem. Please update the application. ### 1/5 — 5 crashes in 1 minute *2022-11-02* Purchased the app and gave it a try, iPhone 13 Pro with iOS 16.1. Didn’t fetch time or location, and tapping into the fields to enter data manually abruptly ended the app, repeatedly. Obviously, not updated on the newest OS version. I‘m asking for my money back! **Developer response:** We have just released version 1.3.5 which fixes the problem. Please update the application. ### 5/5 — Sorry and please cancel my previous message *2022-02-05* Dear support, Kindly ask you cancel my previous message and sorry. Before your apps doesn’t work properly. Now all works perfectly. Thanks. **Developer response:** Thank you very much for your update. Best regards ### 1/5 — Won’t open *2021-07-18* App won’t open on iPhone 11 with OS 14.6. I want a refund! **Developer response:** The issue has been corrected. Please update to version 1.3.0 ### 1/5 — Not worth the money *2021-03-14* Took a chance and found it wasn’t worth the money. Zero instructions and no support via the app or on the developer’s website. Spend your money on something else. **Developer response:** Please upgrade to version 1.2. User guide and support have been added. ## Frequently asked questions about Perpetual Nautical Almanac ### What celestial bodies does Perpetual Nautical Almanac track? Perpetual Nautical Almanac tracks the Sun, Moon, Venus, Mars, Jupiter, Saturn, and 99 stars. It provides their precise positions (GHA/dec) and other relevant data. ### Can Perpetual Nautical Almanac calculate sunrise and sunset times? Yes, Perpetual Nautical Almanac can calculate astronomical dawn, nautical dawn, civil dawn, sunrise, sunset, civil dusk, nautical dusk, and astronomical dusk. An estimated elevation value is needed for these calculations. ### What is the price of Perpetual Nautical Almanac? Perpetual Nautical Almanac is a paid application priced at $6.99. This one-time purchase grants access to all its features. ### On which devices can I use Perpetual Nautical Almanac? Perpetual Nautical Almanac is available for iPhone and iPad. It is designed to run on Apple's mobile operating systems. ### How often is Perpetual Nautical Almanac updated? The latest version of Perpetual Nautical Almanac is 2.01, last updated on February 10, 2025. Updates typically include improvements and new features. ### Does Perpetual Nautical Almanac have ads? No, Perpetual Nautical Almanac does not contain advertisements. As a paid application, it offers an ad-free experience. ### What is the age rating for Perpetual Nautical Almanac? Perpetual Nautical Almanac has an age rating of 4+. This indicates it is suitable for users of all ages. ### What is the user sentiment for Perpetual Nautical Almanac? Based on the available data, Perpetual Nautical Almanac has a perfect rating of 5.0 stars from 1 rating, suggesting very positive user sentiment. ## Version history (last 5 releases) ### 2.01 — 2025-02-10 Correction for possible crash when retrieving GPS location. Corrected astronomical sunset & sunrise (duplicated nautical values were being displayed) ### 2.0 — 2024-09-27 Version 2.0 enhancements: - Completely redesigned interface, with several screens that facilitate the use and visualization of data. Compatibility with iPad in portrait orientation. - Now you can enter hours, minutes and seconds when entering the time to perform the calculations, so you can now get the results with second precision. - A function has also been added that allows you to convert the phone's local time and date to UTC in the date entry screen at the touch of a button. - In the dedicated star view, now displays: o Constellation with image. o Hierarchy of the star within the constellation. o SHA and Dec o Apparent magnitude. o Hemisphere in which it is observable. o The list of stars can be sorted by: * SHA * Name of the star. * Name of the constellation. * Apparent magnitude. o The list can be filtered by: * Show all * Only visible in the northern hemisphere. * Only visible in the southern hemisphere. * Visible in both hemispheres. - In the calculations / corrections section, the function to calculate the true bearing of all celestial bodies supported by this application has been added. In this view you can enter the estimated position of the ship and UTC time manually, or by pressing a button retrieve the GPS position of the iPhone/iPad and the time and date of the device converted to UTC. In this way it is quick and easy to calculate the error that the gyro compass or magnetic compass may have. ### 1.3.5 — 2022-11-29 Corrected incompatibility with iOS 16.1 ### 1.3.0 — 2021-08-24 Corrected incompatibility with iOS 14.6 and later versions. ### 1.2.1 — 2021-04-05 Correction of typographical error in support message. ## Apps similar to Perpetual Nautical Almanac | App | Rating | Price | Category | | --- | --- | --- | --- | | [EZ Celestial Navigation](https://appshunter.io/ios/app/ez-celestial-navigation/id1547239240) | 4.9 (26) | $29.99 | Navigation | | [Radar Plotting](https://appshunter.io/ios/app/radar-plotting/id1470598201) | 5.0 (1) | $7.99 | Navigation | | [EZ Nautical Almanac](https://appshunter.io/ios/app/ez-nautical-almanac/id6468887411) | 5.0 (5) | $9.99 | Navigation | | [Nautical Calculator Preview](https://appshunter.io/ios/app/nautical-calculator-preview/id1534074231) | 5.0 (1) | Free | Navigation | | [Celestial Nav](https://appshunter.io/ios/app/celestial-nav/id1569880598) | 4.3 (10) | Free | Navigation | | [Sextant — Celestial Nav](https://appshunter.io/ios/app/sextant-celestial-nav/id6758679821) | — | $9.99 | Navigation | ## Related topics [perpetual nautical almanac](https://appshunter.io/ios/topics/perpetual-nautical-almanac) · [almanac nautical](https://appshunter.io/ios/topics/almanac-nautical) --- *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 2026-08-29.*