Mission Control gives users an easy way to see all their desktops and full-screen windows, in addition to Dashboard and the Dock, at one time. In Mission Control, users can create a new desktop, switch between desktops and full-screen windows, or choose a specific window on the current desktop.
In System Preferences, users can set how they want to enter Mission Control, such as with a couple of keystrokes, a gesture, a hot corner, or all three.
Apps don’t influence the way Mission Control displays the user’s desktops and full-screen windows, but apps need to ensure that users can enter Mission Control whenever they want.
Respect the “enter Mission Control” gesture. No matter which gesture users choose for this action, you need to ensure that it works all the time, regardless of what your app is doing.