A flag is shown and you name the country from four options. A run is fifteen flags drawn from a pool of thirty, and each one gives you eight seconds. Answer or let the bar run out, and the next flag follows straight after.
A correct answer scores 10 points plus 3 for each answer already in your current streak, so answers get progressively more valuable: 10, then 13, then 16, and so on with no ceiling. A wrong answer or a timeout scores nothing and resets the streak to zero. The timer bar drains over eight seconds and a timeout reveals the country before moving on after one second. The pool holds thirty countries across the Americas, Europe, Africa, the Middle East and Asia, and the three decoys are drawn at random from the other twenty-nine, so they are not grouped by region.
The flags are emoji, so they are drawn by your operating system's font. A few platforms, Windows in particular, show country codes instead of the flag artwork.
Thirty in the pool, of which each run shows fifteen. Playing twice covers most of them.
Yes — on a touch screen the game shows on-screen buttons, and games played with a mouse work by tapping.