- How it is possible to delete a piece?
Tap the delete button (in the top-right screen) to activate it, once enabled tap the elements you want to delete, then disable it tapping one of the elements selection buttons.
- How does undo button work?
The undo button (in the bottom-right screen) cancels the last action done to the drawing, that is it deletes the last created element or recreates the last deleted element.
- What does magnetic hook do?
The magnetic hook is a drawing option, you can enable it to facilitate attaching to existing anchor points when you draw a new element.
- Is level 12 missing an anchor point?
No, but it has a non-standard solution, instead of the last anchor point, there's an anchor point on top of the ending bank that allows the sustaining of the last road element.
- How can I improve my score?
You can specially improve it avoiding part breakages, minimizing the stress that the elements of the bridge suffer and using the fewest possible elements. Finally higher difficulty increases total score.