StarPilot vs GPS Anti Spoof Pro

The state-of-the-art solution to navigation computations on your iPhone or iPod touch. StarPilot does celestial sight reductions of all bodies using high-precision internal almanac, plus mathematical and graphic solutions for position fixes, great circle, rhumb line, traverse and composite sailings, all current problems, piloting solutions, and much more...including lunar distance method of finding GMT from the sky and a unique graphical Sight Planner, and the new Sight Analyzer function that helps you get the most accurate results from a series of sights. The StarPilot is the self sufficient state of the art solution to ocean navigation, fully up-gradeable with free upgrades available via Internet download, easy to use operation from logical menu lists, plus illustrated context sensitive help with practice exercises. The StarPilot requires no external resources to complete its computations. Internet access is not required to use this program or to access any of its help files. General program design features... that save time, keystrokes, and minimize errors - Easy to use menu-driven interface - Stored settings of commonly used values - All bodies and star names stored internally, no need for separate lists - DR functions integrated with the celestial functions - Convenient DR updating by log or time - Input courses as true or magnetic - Convenient time input, with or without zone description and watch error - Graphing calculator plots LOPS, Fixes, DR positions, and Star maps - Program can be easily updated to incorporate latest version and features - Custom menu bar for quick navigation to often-used functions Sight Planning - Sunrise, Sunset, times and bearings (amplitudes) - LAN, time, Equation of time, Hs max at LAN1 - Nautical and Civil twilight times, and LHA Aries at midpoint between them - Moonrise, Moonset, Moon phase, and Moon age - Precompute specific values of Hc and Zn for any body - Planet and Star ID by observed height and bearing - SIGHT PLANNER function plots full sky showing moon, stars, and planets in Radar-like display of heights and bearings. Set Hc min/max and max number of stars before computation. Set cursor and click to read the actual height and bearing of a plotted body. - Special fast almanac mode allows full sky plot - Display internal list of 173 stars by name, brightness, and location - Unique BEST SIGHTS function selects the optimum triads of sights for any sky Sight Reduction - Optional modes for sequential sights using repeated settings or unrelated individual sights - Perpetual almanac accurate to 2100+ - Historically accurate almanac data to 16th century - Sight reduction of Sun, Moon, Mars, Venus, Jupiter, Saturn... plus Mercury! - Sight Reduction of 173 stars plus Polaris - “Assumed positions” read directly from DR section without extra input - View intercepts (a-values) with or without course and speed corrections - Full input data displayed with results to check for errors - Special center-body mode for artificial horizon data - Dip-short mode for practice at shorelines Celestial Fixes - Unique SIGHT ANALYZER fits a sequence of sights to the right slope for optimum sight selection - All fixes corrected automatically for course and speed as needed - Fix accuracy independent of DR accuracy in all cases - Plots LOPS with live cursor position display - Fix computed by USNO algorithm in the Nautical Almanac - Zoom in on plot to see where computed fix is located - Fix can be obtained by graphic selection from the LOP plot - Automatic display of DR-to-Fix range and bearing - Optional automatic update of DR after fix - Display new course and distance to stored destination

Instantly compare observed celestial navigation altitudes with high precision, live calculated altitudes. Shoot the Sun, tap pause in the app, and get instant feedback. Standard version includes data for the Sun, Venus, and two stars. The Pro version of the app is for serious navigation use and includes data for the Sun, Moon, Venus, Mars, Jupiter, Saturn, the 57 standard navigational stars, plus Polaris. Both versions function off-network and at sea however the standard version only works for ten days off-network. The Pro version can function for weeks in the middle of the ocean without network access. This app calculates the exact sextant altitude that should be observed in celestial navigation at sea or on land assuming that the GPS position is correct. No paperwork is required, no tables of corrections. All corrections are included automatically: index error, system time error, dip of the horizon, refraction, temperature and pressure corrections to refraction, altitude above sea level, parallax, and also gravitational deflection of the vertical (a correction of up 2 nautical miles not handled by any other celestial navigation sight-clearing product) are all included automatically. If the GPS position is wrong, due to Spoofing at sea, observations will not match. With this app and occasional quick sextant sights, mariners can reliably detect GPS spoofing. No GPS Spoofing? The app also functions as a celestial navigation trainer: take a sextant sight and immediately compare against the app's display. No paperwork and instant feedback will improve celestial sextant skills in hours instead of days or weeks.  The app works off-network, even in the middle of the ocean. If a network connection is available, the app will download temperature and pressure information automatically. Or weather data can be entered manually, if desired. The ephemeris data is generated from the same JPL numerical integrations of lunar and planetary motions used by the official Nautical Almanac and Astronomical Almanac. All coordinates are accurate to one second of arc, and displayed altitudes are accurate to a tenth of a minute of arc.