1. Open the application you want to display in full screen.

2. Find the navigation bar at the bottom of the screen, which contains some commonly used buttons (such as home page, multitasking management, etc.). ).

3. In the upper right corner of the navigation bar, click a small arrow or four triangle indicators. This button is called "Control Center".

4. The control center will pop up some shortcut setting options from the bottom.

5. Find a box icon, which stands for "lock screen horizontally and vertically". Click this icon to switch whether the device automatically rotates the screen.

6. Make sure the box icon is closed to unlock the horizontal and vertical screens. If it is gray, it means that the lock has been unlocked and the application will be able to run in full screen mode. Note that the full-screen display function may not be fully realized in some applications. This depends on the developer's choice and restriction of application interface design.