In Me › Backup & Restore, you can export what's on this device to a single backup file, then restore it after switching phones or reinstalling.
Included: all your dashboards and widget parameters; reminders, plus each tool's reminder level limit and background task switch; installed tools (including ones you authored) and the records they store; appearance and language settings.
Not included: sign-in state and credentials (connect them again after restoring); home screen widgets (add them again after restoring); recent reminders; external app access (after restoring, you'll be asked again the first time a tool opens another app).
Two ways to restore:
With Sync across devices on, what you restore syncs to your other devices, and anything deleted by Replace everything is deleted on your other devices too.