Daylength vs Horizon

The app calculates the time between sunrise and sunset for a chosen date and place anywhere in the world. It is shown in an easy to read manner. The date is picked with a simple calendar. The place is chosen by simply moving the map and tapping it.

Hold up your phone and watch the night sky come alive. Horizon-AR uses your camera, GPS, and device motion to place real-time augmented reality overlays exactly where celestial objects appear in the sky above you. TRACK THE SOLAR SYSTEM Follow the Moon, Sun, Mercury, Venus, Mars, Jupiter, and Saturn with a live arc overlay showing each object's full path across the sky tonight. Rise and set times update in real time based on your precise location. 110 MESSIER DEEP-SKY OBJECTS IN AR Activate Hot Targets mode and see every Messier object currently above your horizon floating in the AR view — galaxies, nebulae, open clusters, and globular clusters, each colour-coded by type. Tap any label to open a detail card showing: • Object type and Messier catalogue number • Common name (Andromeda Galaxy, Orion Nebula, Pleiades…) • Current altitude above the horizon • Apparent visual magnitude • Recommended instrument — naked eye, binoculars, or telescope • Favourite toggle, saved across sessions When objects cluster together, a single tap fans them out radially so you can reach each one individually. FILTER BY OBJECT TYPE Narrow the Hot Targets overlay to just galaxies, just nebulae, or just star clusters with a single tap. Objects you've starred appear in your Nightly Overview for quick access every session. FREEZE THE SKY Long-press anywhere to lock the entire AR view — overlays and camera image — as a still frame. Perfect for star parties, sketching, or sharing a screenshot. Tap once to unfreeze. NIGHTLY OVERVIEW Open the Tonight sheet for a full list of rise, transit, and set times for all solar system objects plus your Messier favourites, sorted for the coming night at your location. WORKS WITHOUT FULL PERMISSIONS No camera access? Horizon-AR switches to a star-field background with altitude rings and an azimuth grid so you can still explore the sky. Declined location? Enter coordinates manually and continue without interruption. No account. No subscription. No ads. Privacy: your location and camera data never leave your device.