Accessibility in Power Apps
I introduced accessibility and why it is important in Power Apps here.
Following are blog posts that talk about specific Power Apps controls:
There are a few things that I haven't covered. Like how to set up accessibility on Windows, iOS, and Android. That's because these missing pieces and some more details about all things related to Power Apps accessibility are covered in the official white paper from Microsoft, which can be found here. It is a very long document and my reasoning for writing these blog posts was to prevent you all from going through a 36 page document and find specific pointers for each control in Power Apps. I hope this helps!