Isometry

Forty-eight cardboard nets in six chapters, fifteen story packs from Paris to Tokyo, and a new net every day. On iPhone Duo, the hinge folds.

A flat cardboard net lies on the table. Fold its flaps up one at a time, each to its mark, until it stands as a box.

Isometry is a quiet puzzle game drawn in fine isometric lines. Every level is a real net, and every fold has an angle to find: a wall stands at 90°, a house roof leans at 51°, the faces of a dodecahedron meet at 117°.

FORTY-EIGHT NETS IN SIX CHAPTERS • First Folds: trays, cubes, sleeves and lids • Angles: a wedge, a pyramid, a tent, a barn with a gambrel roof • Order: tuck boxes and pizza boxes, where one flap has to go before another • Pairs: a drawer that slides into its sleeve, a lid that turns over and drops on, a box packed inside a box • Solids: a tetrahedron, an octahedron, a lantern, a dodecahedron, and the Grand Box • Builds: a step pyramid, a gem, a bridge, a keep, a rocket and a skyline

FOLD IT YOUR WAY • On iPhone and iPad, tap a flap and turn its dial, or drag anywhere to lift it. Let go on the mark and it creases. • On iPhone Duo, tap a fold and the flap takes the phone's own angle. Fold the phone to fold the flap, and close it to shut the lid. • Stuck? The lightbulb shows the next fold, for one mark.

STORY PACKS Once the first level is done, the story packs open: objects in several pieces, each folded on its own and then put together, with a line of story to every level. • Paris: a café kiosk, a bookstall by the river, a box of macarons, the Arc de Triomphe and the tower • World Landmarks: the pyramids of Giza, a clock tower, a lighthouse, a pagoda and a windmill • Six more cities: Rome, New York, London, Tokyo, Lisbon and Cairo • And in their seasons, each for its own weeks of the year: Halloween, Christmas, the Lunar New Year, Valentine's Day, Ramadan, Easter and Eid al-Adha

TODAY'S NET A new net every day, the same for everyone. Fold it each day to keep your streak, with today's net on your Home Screen in the widget.

BEYOND THE SCREEN • Print the net of any level on A4, cut it from thin card and glue it up. • Share a picture of what you folded, or a short film of its net folding up. • On your desk: set the finished object on your own table in augmented reality.

THREE MARKS Finish a level without a slip for three marks. A wasted fold, a bump or an undo costs one. Levels open in order as you finish them, and every box you finish stands on the home page's shelves. Your marks follow you to your other devices through iCloud.

ACHIEVEMENTS Sixteen in Game Center: the first fold, each of the first five chapters, full marks, all 120 marks of those chapters, a clean run of five, a level folded by the hinge, and the first six packs.

DRAWN IN HAIRLINE Fine grey lines on white with one orange flap in hand, or, in dark mode, Hairline Night: light lines on black with amber.

No ads, no accounts, no in-app purchases. Plays fully offline.