There are different zones of delivery (in Yandex.the maps, fortunately, there is a handy tool for marking). There is the challenge of getting on the backend corresponding to the address of delivery zone.
To obtain the address coordinates, as you know, is not a problem, but the definition of entering one of the zones was not such a simple task. Found API Yandex designed only for the client part, you can certainly reinvent their bikes. But maybe someone already solved similar problem?