The problem with accelerometers and gyros is they drift badly if you try to derive absolute positioning from them alone. They need to be fused with some other form of tracking to anchor them in absolute space, which in the case of the Quest and Vision Pro is done with multiple outward-facing cameras fed into a SLAM algorithm.
Maybe Cardboard could have attempted to use the phones camera for SLAM, but a single lens would only have got them so far. Dedicated VR headsets have at least four cameras pointing in different directions, which are sometimes augmented by IR projectors and/or LiDAR.
Maybe Cardboard could have attempted to use the phones camera for SLAM, but a single lens would only have got them so far. Dedicated VR headsets have at least four cameras pointing in different directions, which are sometimes augmented by IR projectors and/or LiDAR.