Bridge Builder

Lay the road, brace it with wood, steel and cable, then press TEST and send a vehicle across. Each member is simulated under load, so a bridge holds, sags or snaps for structural reasons rather than scripted ones, and you can watch which parts are working hardest as the truck rolls over.

There are 35 levels in seven chapters, from a 4 m brook up to a 36 m crossing for a forty-tonne semi, with piers, slopes, lattice pylons, flood water, ship channels and rationed materials along the way. The last chapter adds moving parts: drawbridges on hydraulic rams, convoys and toll bolts. The materials behave differently. Wood is light and cheap but buckles under compression, steel takes both tension and compression, and cable reaches far but only pulls.

Each level awards three stars, for getting across, staying under the target cost and keeping peak stress below 75%, plus a bonus goal such as a parts limit or a banned material. After every test, a stress graph shows the load on every member over the whole run, and tapping it finds the weakest link. A level editor lets players set up their own gaps, banks, vehicles, budgets and goals and share them as files.

It was built for touch from the start: drag to build, tap to remove, pinch to zoom, with a magnifier that shows which joint you are placing on. It has no ads, no in-app purchases, no accounts and no data collection.

Written in TypeScript with Vite and wrapped for Android with Capacitor. Available on Google Play.