I haven't used it in a while, but before AR kit, there was already MagicPlan, an app that allows one to record all the corners and locations of door and windows

I haven't used it in a while, but before AR kit, there was already MagicPlan, an app that allows one to record all the corners and locations of door and windows in a house, and then automatically stitch it together into an architectural floor plan, list surface areas per room etc. Measured distances don't have to be recorded very accurately: you can override some measurements with a manually entered number, and a solver adjust everything accordingly. Really very neat if you need to order new tiles for your reflooring project or add a floor plan to the real estate listing when you sell your house. I know some realtors were using that app as well. I imaging that making such an app today is much easier with AR kit. Maybe not your typical killer app, but very useful if you need it.