Would be interested to know about the a11y story on web and other platforms. Does it integrate with screen readers, accessible navigation tools, a11y apis, etc.
This is somewhere quite a few tools fall down. For example, for web: Rendering to canvas doesn't create the dom nodes required to hook into the tools, and creating the nodes appropriately can have a significant performance impact.
What about native a11y tools and tech.. there are some ios specific ones that you'd expect on an ios app for example.