DiBird vs Sextant Navigation

Every birder remembers the first time they spotted something rare. DiBird helps you remember all of them. Log your sightings, explore species checklists, keep field diaries, and see how your life list stacks up against other birders — all in one thoughtfully built app. YOUR SPOTS, YOUR WAY Save your favourite birding locations with precise coordinates, or let DiBird find your current spot automatically. Each place tracks its own stats: how many species, how many observations, which diary entries belong there. Your locations are private — only you see them. A CHECKLIST THAT ACTUALLY HELPS Browse the full species list for any country, broken down by order and family with progress bars. See at a glance what you've spotted and what's still waiting. Jump straight to adding a new observation with one tap. FIELD DIARIES More than a list — write field notes the way birders always have. Group observations into diary entries with dates, locations and free-form notes. Keep them private or share them publicly. STATS WORTH EXPLORING Your personal statistics, filtered by country, location, species or date range. Sort your life list alphabetically, taxonomically, or by when you first saw each bird. See exactly which species you're missing in a given area. COMMUNITY LEADERBOARD See who's spotted the most species in your country this month. Compare your list head-to-head with another birder — shared species, unique finds, the full picture. Friendly competition, no drama. PRIVACY BY DESIGN Make your profile, observations, or diaries private at any time. Public sightings are shown in a shifted 6×6 km area — your exact spot stays yours. Optional Face ID / Touch Id lock - turn it on in Settings to your data private no a shared device. - Smart global filters — set a country or date range once, it follows you across every screen - Light, dark, and auto theme — looks good at dawn or dusk - Fast language switching built right into the menu - Bird of the day for your selected country - Export all your data anytime DiBird is free to download and use.

Sextant Navigation is a celestial navigation primer for sailors, students, and maritime enthusiasts who want to understand the ancient art of finding position by the stars. The app covers the complete foundation of celestial navigation in three focused sections: STARS — Browse 15 of the most important navigation stars used by mariners across the centuries, including Polaris, Sirius, Vega, Arcturus, Capella, Rigel, Procyon, Betelgeuse, Aldebaran, Antares, Spica, Fomalhaut, Deneb, Canopus, and Acrux. Each entry shows the star's constellation, apparent magnitude, and detailed notes on its navigation role — from Polaris as a direct latitude indicator in the Northern Hemisphere to Canopus and Acrux for Southern Hemisphere position work. TOOLS — Learn how the four essential instruments of celestial navigation work: the sextant (measuring altitude above the horizon), the chronometer (providing accurate GMT for longitude), the Nautical Almanac (tabulating body positions for every hour of the year), and the plotting sheet (graphing lines of position to find the fix). Each entry explains both the theory and the practical steps of use. PRACTICE — Work through six realistic sight-reduction problems, each with a named star, an observed altitude, a DR position, a step-by-step reduction showing index error, dip, refraction, GHA, declination, assumed position, computed altitude, and intercept, and a final position fix statement. Problems include a Polaris latitude shot, evening twilight fixes on Sirius and Vega, a dawn fix on Arcturus, a Southern Hemisphere Canopus sight, and a classic three-star fix using Rigel, Sirius, and Betelgeuse. Everything works completely offline. No account required, no ads, no tracking.