Umbra Sphere vs Roamlog

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.

Track your time in every state and country—automatically. Roamlog uses your location to automatically detect when you enter a new state or country and tracks how long you spend there. Perfect for digital nomads managing tax residency, travelers tracking their adventures, or anyone who needs accurate location-based time records. SET IT AND FORGET IT Enable location tracking once, and Roamlog does the rest. The app automatically detects when you cross state or country borders and starts tracking your time—no manual entry needed. • Automatic detection of new locations • Background tracking even when the app is closed • Smart notifications when you change locations • Live tracking tile shows your current location and days count ACCURATE TIME TRACKING Get precise records of exactly how long you've spent in each location, down to the day. • First-and-last day or calendar day counting options • Automatic calculation of total days • Start and end dates for every entry • Add purpose notes to remember why you were there BEAUTIFUL STATISTICS Visualize your travel patterns with clear, easy-to-read charts and summaries. • See how many states and countries you've visited • Bar charts showing time spent in each location • Filter by date range or specific locations • Separate views for states and countries MANUAL ENTRIES TOO Prefer manual control? Add entries yourself for past trips or locations where you don't have location services enabled. • Quick manual entry form • Edit any entry anytime • Add or modify dates and purposes • Works perfectly without location permission if you prefer DRAFT ENTRIES • Automatic drafts when tracking stops unexpectedly • Add purpose and details when convenient YOUR DATA, YOUR CONTROL Complete privacy and security built in. • All data stored in your personal iCloud account • Automatic sync across all your devices • Zero data collection—we never see your information • Delete data anytime PERFECT FOR: • Digital nomads managing tax residency requirements • Travelers documenting their journeys • Anyone who needs to know "How long was I there?" PRO TIPS: • Use "Always" location permission for fully automatic tracking • Add purpose notes to remember work trips vs personal travel • Use date filters to generate reports for specific time periods • Export data from your iCloud account as needed