Once I've developed an app in XD, how can I put it on AppStore and Google Play?
Thanks in advance.
I am not an Xd Xpert, but my understanding is that you would never do that. Xd is for saving you months of programming time while you work out how the app should function. Once there is sign off on how the Xd prototype works, developers would make a real app do the same thing.
Here's an article on how to export your assets so that developers can make the real thing: