When I started building out the new mobile app for Wyztalk there where a few things on my personal ToDo list that obviously had great benefit to the business, one was a CI pipeline (Article) which I recently completed, this one, however, was something I got right quite early on.
With our current Ionic v1 app we needed to roll out a complete app deploy for CSS or Localization updates. While my implementations for both the UI and locale supported simply being hosted, even being small files, not something you want to be sending down the wire unnecessarily.
For the Flutter app, I spent quite a bit of time working on a simple way to implement this, for the localization we are using easy_localization as it was one of the simpler implementations that both supported JSON as well as online locale, something very useful for initial development.
For the UI (CSS) I also opted for a JSON solution as it allowed me more control over specific elements and edge cases which come up more often in a white label product and ended up being beneficial for this problem as well.