Bridge Builder

Will your bridge hold, sag, or snap into the river?

Bridge Builder is a physics puzzle game about building bridges on a budget. Lay the road, brace it with wood, steel and cable, then press TEST and send a vehicle across. Every beam carries real load, and you can see which parts of your structure are working hardest as the truck rolls over it.

35 LEVELS IN SEVEN CHAPTERS

Start with a 4 m brook and work your way up to a 36 m crossing for a forty-tonne semi. Along the way you'll meet piers, slopes, lattice pylons, rock overhangs, flood water, ship channels and rationed materials. The final chapter, Moving Parts, adds drawbridges on hydraulic rams, convoys and toll bolts.

SIX MATERIALS, EACH WITH ITS OWN CHARACTER

- Road and heavy deck for the vehicles to drive on

- Wood: light and cheap, but it buckles under compression

- Steel: strong in both tension and compression

- Cable: long reach, tension only – hang your deck from pylons

- Hydraulic rams: lift a drawbridge so ships can pass

THREE STARS PER LEVEL

Get across, build under the target cost, and keep peak stress below 75%. Each level also has a bonus goal, such as a stress cap, a parts limit or a banned material, so there is always a better bridge to find.

SEE WHY IT BROKE

After each test, the stress graph shows the load on every member over the whole run. Tap the graph to find the weakest link, then fix it and try again.

MAKE YOUR OWN LEVELS

The level editor lets you set the gap, banks, piers, pylons, water, vehicles, budget and goals. Playtest your level and share it as a file with friends.

BUILT FOR TOUCH

Drag to build, tap to remove, pinch to zoom. A magnifier shows exactly which joint you're placing on, and undo is always one tap away.

- Seven scenes, from a river at golden hour to a city at night and a snowy mountain pass

- Tutorial levels with a "watch an example" ghost bridge

- Several player profiles on the same device

- No ads, no in-app purchases, no accounts and no data collection – your progress stays on your phone