Comparing local component state and global application state

If you want to provide some data to be shown in your UI, you must store it in your state in most scenarios. But the interesting question is: In which state? Local component state or global application state?

This is a topic that has no simple answer or rules that fit every situation. However, I want to give you some guidelines so that you can make a good decision for all of your use cases:

• Keep your global state as lean as possible: Global variables are something that is very uncommon to use in most programming languages. And this is for a reason. If everything can be set anywhere in your application, it is hard to debug and maintain it. Also, the bigger the global application state grows, the more likely it is that you will run into performance problems.
• Form data should not be part of the global state: When you provide input fields such as text fields, toggles, date pickers, or anything else, the state of...