The upgrade adds a big new feature to AR developers’ toolset: wall detection. Previous versions of ARKit only focused on horizontal plane detection, meaning that it only able to detect floors for objects to be placed onto. With the new upgrade, AR developers will now be able to add walls into the mix — for instance, creating a game in which you throw darts at a wall-mounted board.
On top of this, resolution is improved so that ARKit will now look at the “real world” in 1080p, rather than 720p. That means that there should now be less disparity between the “fake” parts of an ARKit scene (which, oddly, looked more realistic due to their higher resolution) and the “real” parts, which previously appeared low resolution.
See the full story here: https://www.cultofmac.com/525043/arkit-1-5-upgrade/