Many augmented reality (AR) applications depend on knowing the location and orientation of the user's device. The default is to use GPS-based solutions, but spatial anchors, a newer technique to address this requirement, are also worth considering. Spatial anchors work with the image recorded by the device's camera, using image features and their relative position in 3D space to recognize a real-world location. For this location a corresponding anchor is created in the AR space. Although spatial anchors can't replace all GPS and marker-based anchors, they do provide more accuracy than most GPS-based solutions and are more resilient to different viewing angles than marker-based anchors. Our experience is currently limited to Google's Cloud Anchors for Android, which worked well for us. Somewhat uncharacteristically Google also offers Cloud Anchors for iOS and with Azure Spatial Anchors Microsoft supports even more platforms.
