Cookies are not stored properly in ios simulator
Hope this will help you save some time.
While I am in "http://127.0.0.1:19006" with my classic browser, I am using the following domain with my device: "http://192.168.0.13:19006". But, adding this domain was not enough. I also add to add "http://192.168.0.13" in the domains. I'm not too sure why, but it's now working: the cache works properly in my device.
Here is the line of code that I modified:
cors = CORS(app, resources={"/*": {"origins": ["http://127.0.0.1:19006", "http://192.168.0.13:19006", "http://192.168.0.13"]}}, supports_credentials=True)