Device Orientation
Websites and apps should work whichever way a screen is turned, as some people can’t turn their device.
What’s in it
What is it for?
Think about how you hold your phone. Sometimes you hold it tall (portrait) to read, and sometimes you turn it sideways (landscape) to watch a video.
For some people, turning their device is not an option. A person who uses a power wheelchair might have their tablet bolted to the armrest so it won't drop. If a website forces the screen to be tall, but their tablet is locked sideways, they can't use it. It's like bolting a TV sideways on your wall and being told to just tilt your head to watch it.
How to support it
Websites and apps should work no matter how the screen is turned.
Never use code that forces the screen to stay in just one direction.
Build designs that stretch or stack neatly to fit the screen, whether it is tall or wide.