What is the difference between local state and shared state in Flutter?

Short answer

Local state belongs to a widget or a small feature, while shared state is needed by multiple parts or different screens and requires a clearer owner and scope.

Explanation

Start with the nearest owner of the state; do not lift a value that only one child needs. Make shared state explicit within the boundary of a feature, and keep temporary state such as the selected tab local unless there is a real reason to share it.

Common mistakes

• Putting all state in a global singleton.
• Treating every value inside a screen as app state.

Follow-up questions

• How do you apply lifting state up between widgets?

Sources

• Flutter docs — Ephemeral vs app state