How to use AXBrailleMap and AXBrailleMapRenderer

I can't really answer how to incorporate these functions into a user interface, but from their description, it doesn't seem like these are what you're looking for. They are for representing and rendering two-dimensional grids of braille dots for braille displays that have multiple lines. The word map is not used in the sense of a geographical map of a place, but in a sense used more in math and computer science of a data structure representing something more complex than a list, in this case a grid of braille dots of different heights. Two-dimensional braille displays are very rare; the only one available to the public is the Orbit Slate, with either 3 lines of 40 cells or 5 lines of 20 cells. However, I don't think the Orbit Slate supports AXBrailleMap and it would not be big enough to display a geographical map anyway. The Dot Pad from Dot Incorporation is advertised to support this API, but there is no way to buy it right now. There are also the Graphiti and Graphiti Plus from Orbit Research, but there is no information on whether they support this API or not, and it does not seem to be possible to buy those either. All the other braille displays are only one line, so this API would not work for them. To make a map accessible in braille on iOS would probably be a very difficult task, because you would probably have to just have a big text area with characters meant to convey the structure of the map in braille, and then be able to adapt your representation for different sizes of braille displays (20 cells, 32 cells, 40 cells, ETC), and I am not sure it would be possible to represent a complex map in this fashion even if you let people zoom in and out and hide the smaller details in the larger view and let people display smaller areas with more detail. Apple makes its own maps kind of accessible with Voiceover, but to get an idea of the structure requires moving your finger around the touchscreen and cannot be done in braille.