Summary

Modern devices can display applications in a landscape- or a portrait mode.
The app can limit this behaviour by locking the screen in a certain orientation.

• portrait: Either the normal portrait-mode, or the upside-down version of this
• portrait-primary: Only the normal portrait mode
• portrait-secondary: Only the upside-down portrait mode
• landscape: Either the normal landscape-mode, or the upside-down version of this
• landscape-primary: Only the normal landscape mode
• landscape-secondary: Only the upside-down landscape mode

For the modes portrait and landscape, the screen will still rotate, but only by 180 degrees instead of the normal 90 degrees.