Umbra Sphere vs getm.app

Umbra Sphere is a proof-of-concept app, we use a geospatial technology called "S²Geometry" to store the locations you've visited, identify which country or region they belong to and present them on a map as cleared shadows (umbra). S²Geometry is a geocoding system that divides the Earth's surface into "cells" ranging from 85 million square kilometers to 0.5 square centimeters. These cells are converted into 64-bit integers using the Hilbert curve. Compared with traditional latitude-longitude coordinate system and map projections, S²Geometry is less intuitive, but it avoids significant distortion, delivers globally consistent accuracy, and offers extraordinary indexing and querying performance. With these advantages, Umbra Sphere converts traces into a series integers and stores them in database with appropriate indexes to generate umbra fast in real-time for displaying. It also provides statistical features, presenting the areas of countries or regions you've visited on "visa" cards. Additionally, Umbra Sphere also features a simple S²Geometry visualization tool, allowing you to view S²Geometry cells and their corresponding integer IDs directly on the map. ● Umbra Sphere supports importing these file types: • GPX and KML trace files • Sync files and snapshot files from Fog of World • Backup CSV files from StepLife ● Privacy We respect privacy, and simply do not collect any of your data. All your data are stored in your device. Umbra Sphere does not provide sync feature, you can manually export and import your data.

The world starts covered. Every street, park, and neighborhood you visit stamps a hex tile and uncovers the map beneath — your own fog-of-war over the city. WALK TO REVEAL YOUR MAP Move through the real world to stamp hexes and light up the places you've been. Track how much of your city you've explored, from single hexes to whole neighborhoods, cities, and countries. PIN MEMORIES TO PLACES Tap any hex you've stamped to name it, jot down what happened, and attach photos. "Satay by the sea." "Saturday kouign-amann." The place itself holds the story — not a camera roll you'll never scroll back through. Your map becomes a journal. FOLLOW WHERE FRIENDS HAVE BEEN Add friends by phone number and, once you both approve, see each other's stamped tiles and memories — on the map and in a feed of real places, not posed posts. Discover the corners of your own city that your friends already love. PRIVACY FIRST: WE STORE HEXES, NOT YOUR GPS TRAIL When you stamp a tile, M records only a coarse hexagonal grid cell — never your raw GPS coordinates or a continuous movement trail. Your movements stay yours. M can use background location so hexes are stamped as you move, even when the app is closed. You choose the permission level; the app works in foreground-only mode too.