When should I use the Flask.config vs. use flask.session?
Anything that is static, app-wide, doesn't change much, and has important information for all users, should use config. (e.g. secret keys, options to modify the app from project to project, emails, generic messages)
Session should only be used to store relevant user data as the data is modified through each page. (e.g. user login data, user preferences, user inputs from previous pages)
If you have to save something from Page 1 to Page 5 in your website for that particular user, then use session. Sessions should mainly be used based on the individual user.
Is there a rule for when to use Flask.config vs. flask.session to store variables?