One game. 177 worlds to play it in.

A quiz is a subject: one clock, one map, aimed at a different obsession. Volcanoes. Airport codes. Whisky regions. The streets of Amsterdam. Twelve categories, from the capitals everyone should know to the corners only some people do, and each quiz gets its own illustrated tile.

The Nature category in the Corto quiz collection, with illustrated tiles for Oceans Seas and Lakes, Canyons, Capes and Headlands, Coral Reefs, and Deserts

The family shelf: free in the box

World Cities ships free with the app: 353 questions across the world's great cities, no purchase needed. Alongside it, 10 free learning quizzes cover the countries of every continent, the states of the USA and Germany, the departments of France, and the provinces of the Netherlands. That is classic school topography as a game: if there is a topography test this week, this is the practice. Every wrong tap shows the right answer, and the rank ladder turns repetition into progress.

World Cities quiz tile: capitals and the big names worldwide, 353 questions, Skilled rank

USA States quiz lobby: 10 questions at 10 seconds each, your best score, and how far the next themed rank is — USA States: 10 questions, 10 seconds each, one best score to beat

Learn quiz reveal: Arizona highlighted on the map after a guess — Miss it once, remember it forever

The twelve categories

Classic free quizzes inside

Capitals and cities, country by country. Africa Capitals, Japan Cities, Megacities, Microstates, and the great cities of every continent.

Nature

Volcanoes, glaciers, waterfalls, coral reefs, deserts, national parks, and the rivers of two continents.

Landmarks

World Wonders, castles, bridges, lighthouses, grand railway stations, sacred sites, opera houses, parliaments, theme parks, the world's great libraries and its most famous hotels.

Sports

F1 circuits, football stadiums, Olympic hosts, cycling climbs, ski resorts, surf breaks, great hiking trails.

Trivia

World flags, airport codes, currencies, dialing codes, national mottos. The hard stuff.

Food & Drink

Wine regions, cheese country, coffee origins, whisky trails, Michelin restaurants, famous dishes.

History

WWII battlegrounds, Napoleonic battles, the Silk Road, the Crusades, ancient empires, Cold War sites.

Culture & Screen

Film locations, band hometowns, music festivals, art museums, book settings, Eurovision hosts.

Power & Money

Financial centers, tax havens, tech HQs, stock exchanges, megaprojects, world institutions.

City Streets

Zoom inside one city and tap streets, canals and squares by name. Twenty-five cities are live: Amsterdam, Barcelona, Berlin, Brussels, Chicago, Dublin, Hamburg, London, Lyon, Madrid, Manchester, Mexico City, Miami, Milan, Munich, New York, Paris, Rome, Rotterdam, Sydney, Toronto, Utrecht, Vienna, Washington and Zurich.

Wildlife

Safari reserves, famous zoos and aquariums, one-home animals and the last refuges of endangered species. The living world, on the map.

Eerie Earth

Ghost towns, disaster sites, unsolved mysteries, shipwrecks and the macabre. Dark-tourism geography, spooky not gory.

Every quiz, its own world

All 177 tiles are individually illustrated in Corto's dusk palette. A few of them:

Yours, once

Unlock a single quiz, a whole category, or everything at once. Every purchase is a lifetime purchase, yours forever. No subscriptions, no ads, no consumables. Prices show in the App Store, in your local currency.

Built to keep growing

New quizzes ship regularly. Recent additions include Famous Hikes, Surf Spots, Grand Stations, and Amsterdam, a 258-question quiz covering every named street, canal, and square inside the A10 ring.