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Build bridges, not walls, with X Construction loaded on your Android (OS 2.1 or higher), and then send a train across your creation to see if it holds up under the pressure, or collapses into catastrophe. Representing a real-world twist on the addictive physics-based casual game genre, X Construction uses the materials and building principles of civil engineering as you try out new bridge designs and test their strength with fully loaded trains.

For each of the first 15 Crossing levels, you'll be given a limited amount of supplies to build your bridge, and a limited number of foundation base-points to use as structural anchors. As you lay the girders, concrete and cables down with a touch and drag of your fingertip, you have control over the material's length, to a point. And this is where the puzzling, exciting aspect of the game comes into play: simply placing girders in a random but eye-pleasing manner will likely result in a literal train wreck of a project.

Dream, Build, and Improve
Additionally, seven Free Build Sandbox levels give you the freedom to use as much building material as you feel you need. It's the perfect way to try out new designs before taking them to the Crossing levels, which unlock progressively with each successful bridge built and tested.

If you run out of building materials, but you've spotted what you feel is a flaw in your design, select the undo-arrow to remove your last piece. Zoom in and out with the plus and minus magnifying-glass icons to aid your manipulation and final placement of the building materials. For a more precise approach, select the steel-worker's wrench, tap the object you want to remove, and then select the I-beam icon to place it in a new location.

Engineering Tips
If you've ever picked up a hammer, some boards, and a handful of nails to make something functional, whether it's a simple table or a complicated tree house, you know that making something safe, sturdy and functional is harder than it looks. X Construction is no different, but fortunately the app features several innovative ways of guiding you through the process of making a solid bridge without just taking over and doing it for you.

If you're stuck in a crossing level and your build is continually failing, select your smartphone's menu button to access the help option for engineering advice regarding the specific materials your level is using. It's the games most straight forward way to lend you tips to help you improve your designs. For example, "Concrete endures pressure easily, but breaks under tension. Note also that it is very heavy."

A more subtle and enlightening approach is to dive into X Construction's preferences level and check the Show Stress box. This will tint the specific parts of your bridge in varying degrees of red when they come under stress. Take note of the stress indicators when you send trains across the gaps, gorges and rivers, even if your build succeeds. This visual feedback will guide you, through trial and error, to have the simulation show as little stress as possible, thereby improving your overall skill in the game.