MagVar vs Meridian Nav

MagVar is targeted towards anyone interested in navigation. This includes, pilots of aircraft, captains of sea going vessels, cartographers, engineers and surveyors. Anyone who uses maps and a compass will find the declination calculation (also referred to magnetic variation) very useful. (Declination is the difference between true and magnetic north and used when plotting a course on a map.) MagVar calculates the magnetic flux density for any location on the Earth and then uses this data to calculate magnetic variation. The model is accurate for dates ranging from January 1, 2025 up through December 31, 2029. Using the model, the app calculates declination and inclination. As the user pans the map, the magnetic variation is calculated and graphically shown as a map overlay.

Meridian is a celestial navigation toolkit built at sea by a working deck officer — fully offline, because mid-ocean is exactly where you need it. SIGHT REDUCTION Compute Hc, Zn and intercept for the Sun, Moon, four planets and 63 navigational stars. Enter your DR position, date/time and sextant altitude — get your line of position. COMPASS ERROR Check gyro error by azimuth of any celestial body — the daily routine, without the almanac and tables. Magnetic variation (WMM2025) is built in for magnetic compass work. STAR FINDER A polar sky-dome view shows exactly which bodies are observable right now from your position — plan your twilight sights before stepping out on the bridge wing. Includes an azimuth-scatter view for picking the best LOP geometry. SUN / MOON Rise, set, meridian passage and twilight times for any position and date. MARINE CHART — FULLY OFFLINE A custom offline vector chart with world time-zone (ZD) boundaries, DST awareness, ports and waypoint routes. Import route files (.rtz / .rou) straight from your ECDIS. CLOCK PLAN Generate the entire voyage's retard/advance schedule from your route — including DST transitions and solar-zone departures. Reorder or edit the changes, then export a clean calendar-style PDF or Excel notice, ready to post on board. UNIT CONVERTER The conversions a navigator actually uses, in two taps. ACCURACY & VALIDATION Every body — Sun, Moon, planets and 63 navigational stars — is cross-checked against JPL ephemeris data (the same source behind the official Nautical Almanac) to arc-minute agreement. Star positions are computed for the current date from the ESA Hipparcos catalogue. Sun azimuth verified at sea against a ship's bridge calculator, and against NOAA's solar calculator (0.000° difference). MADE FOR Deck officers who want a fast backup and sanity check, cadets and officers studying celestial navigation, and anyone who believes a navigator should still be able to find a ship without a satellite. No account. No ads. No subscription. No internet required. One-time purchase. IMPORTANT Meridian is a reference and training aid for celestial navigation. It is not a certified navigation system and does not replace official nautical publications, charts, or type-approved equipment.