A new app called Walkabout3d Mobile allows Google SketchUp users to generate and view panoramas of their designs directly on an iPhone or iPad.

Visitors to a building site can view a 3D model for a future design created with SketchUp, overlaid on the landscape. They can check if the design will overlook their property, block out sunlight, or become an eyesore.

Unlike some augmented reality apps, this one doesn’t actually let you virtually walk through an area, says Ed Morgan of Deliverance Software. This is because 3D models are often extremely large files, far too big for a mobile device to continuously update in real time.

The digital compass and GPS locator on an iPhone or iPad let users view virtual, static 3D panoramic views of a site downloaded to their devices over a 3G network, says Morgan.

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