You can use the `BoxWithConstraints` widget, which...

# compose

[jim]

You can use the BoxWithConstraints widget, which allows you to get information about the size constraints, including the amount of space available. Among other things, this allows you to check when width is greater than height or height is greater than width, and thus you can track what is effectively the definition of a rotation.

You could write a widget to encapsulate this behavior, and use that widget at the root of your app. We don't have an out-of-the-box widget that will perform the type of animated rotation that I think you might be imagining, but it shouldn't be hard to write one, and I'm sure the community would be grateful if someone publishes such a thing on github or whatever!