I am an architectural draftsman looking to make an app that will put 3d models of houses into the real world. This would be great for homeowners, architects and planners. What is the best/most promising development environment for geospatial intelligence in the outdoors? I would imagine the phone would need to scan its environment and match it up to google earth or street view info in order to understand exactly where it is in the world... is that technology here yet? Is it close? How should I begin working on this thing?