Specifications

What's under the hood

Platforms, distribution formats, data sources, and system requirements.

Platforms & formats

SystemFormatStandard editionPro edition
Windows 10 / 11.exe (installer)113 MB118 MB
Linux (any distribution).AppImage122 MB129 MB
Linux (Debian / Ubuntu…).deb113 MB118 MB
Linux (Fedora / openSUSE…).rpm untested119 MB125 MB
Android 7.0+ touch.apk123 MB130 MB
ℹ

The .rpm package is provided but its installation has not been tested by the author — see the FAQ. The Android .apk is not distributed on the Google Play Store (install via "unknown sources") — see the FAQ for details.

Data sources

DomainSourceLicence
Planetary ephemeridesANISE (Nyx Space) / JPL DE (NASA-JPL)MPL-2.0 / public domain
Stars & constellationsd3-celestial / Stellarium — 88 IAU figuresBSD
Worldwide tides ProTICON-4 (DGFI-TUM, GESLA-4) via the Neaps database — 4,170 stationsCC BY 4.0
Magnetic variation ProWMM — World Magnetic Modelpublic domain
BasemapNatural Earthpublic domain

Background stars and constellation lines are shown in simplified geometric position (no refraction or dip); the Sun, Moon, planets and navigation-star catalog use the software's usual precise positions.

GPS connectivity Pro

Serial port

Wired NMEA 0183.

UDP network

NMEA 0183 via multiplexer.

NMEA 2000

Fast-packet frames (PGN).

SignalK

WebSocket, SignalK deltas.

A built-in GPS simulator can emit these same protocols (UDP NMEA 0183, NMEA 2000, SignalK/WebSocket) to test reception without any connected hardware. On Android, only network sources are available (no serial port on a tablet).

Full Standard / Pro comparison

FeatureStandardPro
Ephemerides (Sun / Moon / planets / stars)✓✓
Observed fix (sight reduction, Polaris, meridian passage, body ID)✓✓
Dead reckoning✓✓
Route — rhumb-line / great-circle / composite✓✓
Lines of position + SHA-256 chained logbook✓✓
Error budget✓✓
Paper reduction worksheet + backup almanac✓✓
Compass check (azimuth / amplitude)✓✓
Conversions, Definitions, solar eclipse✓✓
Printable manual, session autosave✓✓
GPS reception (serial / UDP / NMEA 2000 / SignalK) + simulator—✓
Worldwide offline tides (4,170 stations)—✓
Plotting sheet (secant Mercator) + world map—✓
Man overboard (MOB) with staleness check—✓
Compass deviation — full table and curve—✓
WMM cross-check (magnetic variation)—✓
Enhanced visual theme (egui-phosphor icons)—✓

Language & design

🦀

Written in Rust

A native application, with no external runtime dependency and no internet connection needed to run.

💾

Automatic autosave

The session (positions, observations, settings) is saved automatically as you work.

🧪

Self-test panel

An internal validation panel, reachable from the Help tab, lets you check the consistency of the calculations.