A city game on your phone about everything you always walk past. When you reach a pearl, the app asks about a detail you'll only see if you look closely.
Look again
Everyone knows the girl with the pearl. Look closely and you'll find dozens more: a stone with two mistakes, a church in hiding, a king who wasn't. Turn a card over.
How it works
The app follows you on the map and taps you on the shoulder as soon as you reach a pearl. Pick one of the four routes, or wander on your own: the compass at the bottom points to the next pearl.
Every pearl comes with a spotting question. The answer lies in a detail on the spot: a year on a house front, an animal on a stone, the way a statue is facing. Looking it up won't help; looking will.
A right answer paints a Delft blue tile into your tile panel, stroke by stroke, with the story behind it. Complete a set and you earn a medal too.
Then and now
Nine paintings, prints and old photographs hang in the app on the very spot where their maker stood, in a little gilt frame with a fan showing which way they looked. Hold up your phone and the image hangs life-size over today's city.
A slider blends then and now into each other. Stand in the right spot, facing the same way, and you've found the view: fifty points, and a story about what has changed since.
Photos of today: Szilas (CC BY 4.0) and Ludvig14 (CC BY-SA 4.0), via Wikimedia Commons, cropped. Old photos: Photoglob Zürich, public domain. Seven more places in the app, including Vermeer's View of Delft and The Little Street.
Delft in 1649
Joan Blaeu drew Delft in 1649, five years before the Delft Thunderclap, the gunpowder explosion of 1654. In the app his map lies over today's city, bent into place at 47 points along the canals, so that his streets fall on yours. Go on, move the glass over the city.
Today's map: © OpenStreetMap contributors, OpenFreeMap. Joan Blaeu, Delft, 1649: Rijksmuseum, public domain.
On the way
One tap and the app walks with you: the map turns with the way you're facing and a voice calls out the turns, so your phone can stay in your pocket. Rather go as the crow flies? Tap the needle and a Delft plate with a compass rose points out the pearl.
Just arrived? Say where you need to go, and the app turns it into a walk with a ten, twenty or forty-minute detour past pearls.
Scan the code and you're playing. Add it to your home screen and it works without signal too: by then the map of the old town is already on your phone.
Your finds and location stay on your phone. Only in a tour does the game leader see where the teams are, and a tour is deleted three days after it ends.
At the Stolpersteine (stumbling stones) there are no points and no quiz. The app tells you the names and gives you a moment of silence.
Walk together
As game leader, you set up a tour in a minute. Teams join with a QR code; you open the stops, ask quiz questions against the clock, send flash challenges and call everyone to a meeting point. At the end there's a winners' podium.
23 minutes to go. Next stop: the Oude Kerk.
Cities
Delft is the first. Which city comes next is partly up to you: suggest your own city, or build it with us if you work for a city, a museum or a hotel.
Scan the code with your phone, or tap the button if it's already in your hand. Free to play for now, no account needed.