
This update contains a new feature: Production donation.
You can now link cities together, donating the production from one to another. This allows you to focus your production efforts on your most valuable or needed cities. You get the card to do this as an option when any city produces.
The production routes can be freely placed and removed, refunding the card to your hand. So you're free to optimise your setup.
There are still some issues with production, however. Notably it takes a long time to produce in high tier cities, often leaving you with turns where you can't do anything. The next update will address this, along with a bunch of new and improved upgrade cards.