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Perpetual Nautical Almanac

by RPA Technologies

  • Navigation
  • Paid
  • Small & simple · 100
View on the App Store
Rating
0.0
0 ratings
Top 86%among 116 Navigation apps
Last update
Sep 21, 2026
Version 2.5
Size
27 MB
Category
Navigation
Tracked since
Oct 9, 2026

Estimated revenue

A model estimate with a likely range, not a reported figure.

$1.9K/ month

Monthly gross store revenue (USD)

Estimated

Where this falls on the revenue bands

Likely range
$240–19K
<$10K
Confidence
Low confidence
Chart day Oct 25, 2026
From Navigation grossing #53

Unverified model estimate. Neither Apple nor the developer has published this number, and the real figure can be several times higher or lower. Low confidence: the real figure can be a band higher or lower.

How this estimate is made

Rank: we take the app's best Top Grossing rank on the latest chart day. Category ranks are converted into an equivalent overall rank, because a #10 in Finance earns far less than a #10 overall.

Curve: that equivalent rank is read off a rank-to-revenue curve anchored on public company revenue and market-data reports for the US iPhone App Store.

Country: the curve is scaled per country (Japan is roughly a third of the US, Türkiye under 1%). Where we have no scale, such as China, there is no estimate.

Range: the likely range widens with country, category and chart depth. It is a plausible span, not a statistical confidence interval.

Not included: ads, payments outside the App Store, and any difference between gross sales and what the developer keeps. Low confidence means indirect data; medium means several independent sources agree.

Full method

Screenshots

As shown on the App Store listing.

About this app

Text from the App Store listing.

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.

What’s new

Release notes for the latest version, as written by the developer.

v2.5

Tested with iOS 27.1, now compatible with iPad and Mac Catalyst

Rank history

Daily position in the South Korea charts. #1 is at the top.

Best rank
#4
Current rank
#6
Days charting
7 of 7

On the charts today

Small & simple score

How realistic it is for a small team to build something like this.

100/100

Small & simple

  • Developer size100% · 25

    Developer: 1 app on the charts

  • Audience size100% · 20

    Ratings: 0

  • App size100% · 10

    Size: 27 MB

  • Price model100% · 15

    Price model: paid

  • Demand proof100% · 30

    Best rank #4, 17 countries

An indicator, not a fact. We can't see team size. Calculated Oct 25, 2026 · method i2

How the score works

Version history

  • 2.5LatestReleased Sep 21, 2026