How to make the "iPhone 6" screen upside down?

1. Open the screen of iPhone6 and slide up from the bottom of the screen with your finger.

Then you can open the control center. In the upper right corner of the control center is the switch for screen rotation.

3. Click it to turn off screen rotation, and click it again to turn on screen rotation.

In layman's terms, this depends on the APP. Look at the screenshot. See, upside down? If there is no hook when developing an application, it is impossible for users to turn the application upside down. Under normal circumstances, 99.9% of iPhone applications have no upside-down function. Apple also does not recommend developers to do so.