DepthViewer can load any Portrait Mode photo with Depth Maps taken with iPhone X and iPhone 7 Plus and show a 3D model of the image.
It will show you the Depth Map in a Black/White image as well as a completely interactive 3D scene that you can zoom and rotate.
Depth Maps are embedded in photos taken with Portrait Mode on the Camera app of iOS devices. You can load HEIC/JPEG images with Depth Maps in the DepthViewer app or directly in the Photos app with the DepthViewer Photos extension.
Note: To export Portrait Mode photos with Depth Map in macOS from the Photos app use the menu File > Export > Export Originals.