@jerry33 said it well.
Creating an industrial strength API...is a major task/....QUOTE]
certainly true. However, in the specific case of Waze, that is avGoogke product and Googke is the Tesla mapping supplier, so that should not be such a gigantic hassle, with, at least LTE cars having enough data speed to deal with the Waze interactive reporting features and fast updates. For true third party apps in general I suspect they'll be quite limited even after the Model III