A handheld device has a projector that projects a pattern of light onto an object, a first camera that captures the projected pattern of light in first images, a second camera that captures the projected pattern of light in second images, a registration camera that captures a succession of third images, one or more processors that determines three-dimensional (3D) coordinates of points on the object based at least in part on the projected pattern, the first images, and the second images, the one or more processors being further operable to register the determined 3D coordinates based at least in part on common features extracted from the succession of third images, and a mobile computing device operably connected to the handheld device and cooperating with the one or more processors, the mobile computing device operable to display the registered 3D coordinates of points.