I suppose there is no point arguing what it *could* do, we know what it does do. Still, I'm going toMy point about shaking the phone covering the camera and running around, is that it can relocalize using purely visual information after it has lost track of its location even after being fed lots of garbage inertial data. It makes sense that it can do this, that's what SLAM does.You wouldn't need to track in the background for this work, but you would have to ensure that the visual landmarks and map aren't deleted when the phone is backgrounded. Neither the video nor the documentation makes it sound like the phone can't relocalized. In fact, the run options make it sound like the opposite is true. What is the point in `resetTracking: false` if it never relocalizes? In fact, what's the point of `pause` if it behaves like `stop`?Lastly, I'm not saying it wouldwork, but most definitelywork a lot of the time. This is a core feature of SLAM.I've submitted a bug report to Apple, we'll see if they think its a bug.