There is no solution to this problem yet, because, as the other answers said, iOS is not supported. Also, there are no libraries for react native that are supporting Azure Maps.
My workaround was to use React Native Maps as the map provider, and just do a backend call to the Azure Maps route provider.
In this way, I just draw the route provided by Azure Maps on the React Native Map.
Hopefully this will help some other people that are trying to use Azure Maps.
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