Comparison

Celestial Navigator vs Nautical Calculator Preview

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Celestial Navigator

This app assists with celestial navigation training by providing a perpetual almanac, star finder chart with animation, and tools for calculating lines of position and meridian passages. It can utilize device sensors for real-time chart positioning, though a marine sextant is still required for actual navigation.

Highlights
  • Perpetual almanac
  • Animated star finder chart
  • Line of position calculation
  • Meridian passage calculation
  • Real-time sensor integration
  • Celestial object data
Features
Read full description

Celestial Navigation Calculator with - perpetual Almanac - star finder chart with animation. Use phone sensor for altitude. - calculation of lines of position ( intercept/delta ) - celestial object data - meridian passage calculation - running fix support - astronomical position calculations with two or more altitude observations - Hipparchus 150 star catalog - World chart with lines and position Program can be set to use device's sensors (gyro, compass) to position the star finder chart in real time. Capture celestial object approximate altitude. Correct Altitude with a Marine Sextant reading (not included). You still need a marine sextant to do celestial navigation, but the phone sensors may be used for training. Software for iPhone and iPad, with the same features. e-book with manual and celestial navigation tutorial.

About

Nautical Calculator Preview

This app provides comprehensive tools for marine navigation, including real-time ship movement, route planning, and advanced sailing calculations. It also offers features for collision avoidance, maneuvering, and learning maritime regulations and signaling.

Highlights
  • Real-time ship movement
  • Route planning
  • Mercator and Great Circle sailing
  • Collision avoidance
  • Maneuvering calculations
  • COLREGs and maritime signaling
  • Offline GPS
Features
Read full description

The application to assist in solving the most important marine problems. - For Marine Navigation +Real-Time Ship Movement; +Route Plan; + Mercator Sailing. + Greate Circle Sailing. + Meridional parts. + Plane Sailing. + Traverse Sailing. + Wheel over. + Current and wind sailing. + Allowing for current and wind. + Calculate true wind and apparent wind on a ship running. + Nautical Almanac + Two Lop Fix + Three Lop Fix + Correcting marine sextant altitude of sun and stars. + Probability Distribution Function. + Standard Deviation and Error. + Offline GPS. - For Maneuvering : -Avoid collisions -Change of station in cases: + with time specified + with speed specified + with course specified + Course and speed of another ship. + Closest point of approach(CPA). + Ability to reach another ship going faster. + Close or open to another ship in cases : - as quickly as possible. - on a constant bearing. - with time specified. + Maneuver to intercept a target ship going faster. + Maneuver to intercept ahead a target ship. + Close to another ship as close as possible. +Keep watch for a target ship within a range of distances; +Maneuvering with added calculating of turning. +Bearing and distance to another ship in advance. - For Learning : +International regulations for preventing collisions at sea (COLREG) include Rules; Lights signs; Shapes signs and Sounds signs. + Marine signalizations include Flag signaling; Morse signaling by hand; Morse code. + Maritime buoyage system. + Unit Conversion for Maritime. + Glossary of Marine Navigation. +Maritime Theory. +Global Lighthouses System. author Vu Cong The. vucongthe@gmail.com - Các tính toán hàng hải và vận động tàu, bao gồm : +Dịch chuyển của tàu theo thời gian thật; +Lập kế hoạch hành trình; +Hành trình theo hải đồ Mercator +Hành trình theo cung vòng lớn. +Vĩ độ tiến +Dự tính vị trí tàu một hướng và nhiều hướng. +Tính và đè độ dạt gió dòng. +Tính toán lượn vòng của tàu. +Tính toán gió thực và gió biểu kiến trên tàu đang hành trình. +Lịch thiên văn hàng hải. +Phương pháp hai đường vị trí. +Hiệu chỉnh độ cao mặt trời và sao đo bằng sextant hàng hải. +Tính hàm phân phối xác suất. +Tính sai số chuẩn và độ lệch chuẩn. +Hướng đi, vận tốc của tàu mục tiêu. +Tránh va. +Các thông số ở điểm tiếp cận CPA. +Các thông số trận địa với thời gian hoặc khoảng cách cho trước. + Xác định khả năng tiếp cận tàu mục tiêu có vận tốc lớn hơn. +Thay đổi khoảng cách tới một tàu khác với : - Thời gian ngắn nhất. - Thời gian cho trước. - Phương vị không đổi. +Vận động cắt mũi hoặc lái một tàu mục tiêu có vận tốc lớn hơn. +Vận động cắt mũi một tàu mục tiêu. +Tiếp cận một tàu khác ở cự ly ngắn nhất. +Tính các yếu tố trận địa với thời gian hoặc cự ly cho trước. +Thay đổi trận địa trong các trường hợp: -với thời gian cho trước. -với vận tốc cho trước. -với hướng đi cho trước. +Vận động trong dải khoảng cách. +Tính toán lượn vòng trong vận động. -Tra cứu hàng hải bao gồm : + Qui tắc tránh va quốc tế (COLREG) : Nội dung các điều luật, Tín hiệu đèn, Dấu hiệu, Tín hiệu âm thanh +Thông hiệu hàng hải : Thông tin cờ hiệu, thông tin cờ tay, mã morse +Hệ thống phao tiêu hàng hải +Thuật ngữ Tiếng Anh Hàng hải. +Chuyển đổi đơn vị trong hàng hải. +Lý thuyết hàng hải. +Hệ thống hải đăng toàn cầu. Các giao diện hiển thị hai ngôn ngữ : Tiếng Anh và tiếng Việt Tác giả : Vũ Công Thế. vucongthe@gmail.com

Screenshots

Celestial Navigator4 screens
Nautical Calculator Preview4 screens

Verdict

The call

The clearest difference is rating: Nautical Calculator Preview at 5.0 against Celestial Navigator's 2.0. Nautical Calculator Preview also leads on update cadence (every 3 weeks vs every 9 months). Celestial Navigator's advantage is ads (none vs shown) and monetization model (free vs ad-supported). On price, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Nautical Calculator Preview holds the better App Store score, 5.0 against 2.0. Both are backed by a comparable volume of ratings — 3 and 1 respectively.

UpkeepUpdate frequency

Celestial Navigator ships an update every 9 months, Nautical Calculator Preview every 3 weeks. The most recent releases landed on August 12, 2026 and August 7, 2026 respectively.

Scorecard6 real differences · 4 level
Celestial Navigator versus Nautical Calculator Preview: the parameters behind the verdict, then further details
ParameterCelestial NavigatorNautical Calculator Preview
PriceFreeFree
Rating2.0 (3 ratings)5.0 (1 ratings) — better
Positive reviews42.9% of reviews—
Number of ratings3 — better1
Update frequencyEvery 9 monthsEvery 3 weeks — better
AdsNo — betterYes
In-app purchasesNoNo
MonetizationFree — betterAd-supported
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS11.0 — better13.0
Further details — not scored
Size32 MB36 MB
Age rating4+4+
DeveloperOmar reisThe Vu Cong

Customer experience

Celestial Navigator

All ratings3 ratings
Positive33.3%
Neutral0.0%
Negative66.7%
Written reviews7 reviews
Positive42.9%
Neutral0.0%
Negative57.1%

Nautical Calculator Preview

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Celestial Navigator

No in-app purchases

None

Nautical Calculator Preview

No in-app purchases

Questions

Is Celestial Navigator free?
Celestial Navigator is free to download, with no in-app purchases.
Is Nautical Calculator Preview free?
Nautical Calculator Preview is free to download, with no in-app purchases.
Which has better reviews, Celestial Navigator or Nautical Calculator Preview?
Nautical Calculator Preview is rated higher. Celestial Navigator averages 2.0 out of 5 from 3 ratings, while Nautical Calculator Preview averages 5.0 from 1 ratings.
Do Celestial Navigator or Nautical Calculator Preview have ads?
Nautical Calculator Preview shows ads; Celestial Navigator does not.
Which is updated more often, Celestial Navigator or Nautical Calculator Preview?
Celestial Navigator ships an update every 9 months, and Nautical Calculator Preview every 3 weeks. Most recently, Celestial Navigator was updated on August 12, 2026 and Nautical Calculator Preview on August 7, 2026.

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