Create an AR app able to open KMZ/KML files

I'm planning to have an AR/VR mobile app that can open the KMZ/KML files. The app will use the camera and GPS of the mobile device and show the KMZ/KML file on the screen. The kmz/kml file will include lines and the app should be able to draw buffer around the lines and the user should be able to manually enter the buffer zone width. The buffer zone transparency or color or the buffer zone span should be adjustable. The construction contractor will use this app to excavate the soil and will use the kmz/kml files to locate the area and the buffer zone to determine the width and length of the excavation. Please see the pdf file attached.