Apologies for the delay on getting back to this post. I hope you all had a nice holiday.
A few things before I put together a description of my workflow and experience in moving from Pythonista to Xcode, to an iOS App in the store:
a) as others have before, I managed to get an App in the store using Pythonista. It is a simple and free drawing app that I made with my kids - similar to one other forum contributor, if I remember right. You can see for yourself at https://itunes.apple.com/us/app/drawing-with-sonia/id925557850?ls=1&mt=8
b) As I mentioned earlier, the current pythonista library in Xcode, as far as I can tell, doesn't support 64-bit. This is a bigger issue, because as of February 1st, Apple will not accept any new apps that don't support 64-bit. As of the summer, they won't accept any updated apps that don't support 64-bit. So we have a very rapidly closing window here, unless the next version of a template comes with 64-bit support.
c) @omz, is there a plan to release another Xcode template soon that will have 64-bit support? If not, then much of this discussion is void (see bullet point b). If you are hesitant about this, @omz, please know that we all appreciate all the effort you've already put into Pythonista. And I probably can speak on behalf of others, when I say that those interested in export to Xcode, would be willing to pay extra (Paypal, or In-App purchase) to have an updated template.
Once we have c), primarily, addressed, I think that we can move on to answer the question. I am a bit weary of spending more time putting this info together, if it is not supported for more than 3 weeks down the road, as I'm sure you can understand.