Our take
Each daily challenge shows five historic photographs. For each one you drop a pin on the world map and pick a year, and the closer you get in place and time, the more points you score, up to 50,000 for the five. It is detective work: shop signs, cars, clothes, light and landscape all carry clues.
It is one of the best history toys online. A street scene that looks like the 1970s turns out to be the 1950s, or a market you would place in Europe is in South America, and every reveal teaches you something. Random games, an archive and community-made sets are there for more.
There is also live multiplayer against friends or strangers, with chat and direct messages. It has mute, block and report tools, but it is a different, faster thing from the quiet daily five.
A first sitting
Look at the photo for a full ten seconds before touching the map. Read every scrap of writing, then decide the continent first and the decade second.
Where to stop
The daily challenge ends after five photos with a score screen: a tidy stopping point. Ranked multiplayer has weekly divisions, streaks and a countdown to the next daily, which are the parts designed to keep you there.
Worth knowing
- An account is for over-13s; younger players need a parent's consent.
- Photos you upload to make your own games can keep their date and location details and may be shown publicly.