Best practices
Support full-screen mode when it makes sense for your experience.
If necessary, adjust your layout in full-screen mode, but don’t programmatically resize your window.
Continue to provide access to essential features and controls so people can complete their task without exiting full-screen mode.
Except in games, let people reveal the Dock while your iPadOS or macOS app is in full-screen mode.
After people switch away from your full-screen experience, help them resume where they left off when they return.
Let people choose when to exit full-screen mode.
Prioritize content by temporarily hiding toolbars and navigation controls.
Platform considerations
iOS, iPadOS
Consider deferring system gestures to prevent accidental exits in a full-screen app or game.
macOS
Use the system-provided full-screen experience.
In a game, don’t change the display mode when players go full screen.
Always let people choose when to enter full-screen mode.
For the complete guidance, including worked examples and illustrations, see the canonical page: https://developer.apple.com/design/human-interface-guidelines/going-full-screen