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Explore global population data like never before. Watch the world's population tick upward in real time, spin a 3D globe, tap any of 197 countries, and dig into demographics, economy, religion, and what comes next — all in one meticulously crafted app. LIVE WORLD POPULATION A running count of everyone alive, updating by the second and in sync on every device — with the births, deaths, and net growth behind the number. Pause it whenever you like. INTERACTIVE 3D GLOBE Tap countries directly on a colour-coded globe. Fly to any nation and explore population, GDP, religion, ethnicity, migration, and age distribution. TIME MACHINE Watch the world transform from 1950 to 2050. Slide through a century of population change, record the animation, and share it. COUNTRY BATTLE Put any two countries head-to-head across key metrics, and share the result cards on WhatsApp, X, or Instagram. GLOBAL RANKINGS Rank every country by GDP, population, GDP per capita, growth rate, density, land area, and more — with instant search and sorting. VOTING & ELECTIONS • US: state-level voter registration, turnout, and Congressional district maps • India: 2024 General Election results by state and constituency, with demographic overlays POPULATION PYRAMIDS Age and gender breakdowns for every country — watch the shape shift decade by decade with the Time Machine. DID YOU KNOW? More than 1,300 facts drawn straight from the data, covering all 197 countries. The set changes every day, and the app remembers what you have already read — so there is always something new. GEOGRAPHY BEE Test your world knowledge with dynamic questions on capitals, landmarks, rivers, and exports — with smart answer masking, so no question gives itself away. GEO-TUTOR Ask an AI tutor anything about geography: rivers, borders, languages, exports. Conversational answers with follow-up suggestions. RELIGION & ETHNICITY Religious composition and ethnic demographics for every country, with historical trends and regional comparisons. STATE-LEVEL DEEP DIVES All 50 US states plus the District of Columbia, and all 28 Indian states plus 8 union territories — population, GDP, voting patterns, gender demographics, and election phases. BUILT FOR EVERYONE Full VoiceOver support, Dynamic Type, Reduce Motion, and pinch-to-zoom throughout. Every control is named and reachable. DATA YOU CAN TRUST Curated from the world's most authoritative sources: United Nations · IMF · World Bank · US Census Bureau · Pew Research · Election Commission of India · CIA World Factbook — No account. No ads. No tracking. Works offline. Just data, beautifully presented.

Three bodies. Countless paths. Watch the beauty of gravity unfold. Three-Body Simulation brings abstract celestial motion into a world of orbits you can watch, interact with, and explore. See three bodies pull on one another as their trails gradually draw patterns, and discover how a simple law of gravity produces rich and fascinating motion. Explore 16 classic periodic solutions From the flowing Figure Eight to Butterfly, Moth, and Bumblebee, discover the shapes and rhythms of different periodic solutions. Detailed introductions to each orbit explain the motion behind these patterns. Discover 10,059 three-dimensional periodic orbits Explore published spatial periodic solutions and discover paths that weave and curve through space. Choose an orbit by number or discover one at random, then rotate the view to see its shape from different directions. Try your own gravity experiment Adjust the mass, initial position, and velocity of each body and watch how the orbit changes. You can also explore random three-body motion to see how the bodies approach, circle, and move away from one another. Turn curiosity into understanding Learn about the origins, history, and basic principles of the three-body problem. See the full system of three equations of motion, explore classic periodic solutions, and learn how the 10,059 spatial periodic orbits were discovered. Let the paths you see become a starting point for understanding gravity and motion. Available on iPhone and iPad in ten languages, including Chinese, English, and Japanese. Orbit data, simulations, and introductions are included in the app, so the core exploration experience works offline. The complete orbit catalog, random motion, and custom experiments are unlocked with a one-time in-app purchase.