When SwiftUI shipped earlier this fall, it didn’t provide any APIs to use the newly introduced inset style for grouped lists and table views. The latest release seems to have addressed that, albeit silently and not in the way that I had expected.

As of iOS 13.2, grouped lists will use the inset style when the horizontal size class environment value is .regular, such is the case with fullscreen scenes on iPad.

If you want to forcibly enable or disable this style, you have to manually set the size class environment variable, preferably directly on your list to avoid any unintended side effects:

List {
  Text("Item 1")
  Text("Item 2")
  Text("Item 3")
}.listStyle(GroupedListStyle())
// To enable the inset style
.environment(\.horizontalSizeClass, .regular)
// To disable the inset style
.environment(\.horizontalSizeClass, .compact)

While I am not aware of any issues caused by this approach, I’d have preferred if Apple introduced a dedicated InsetGroupedListStyle or, even better, exposed the underlying ListStyle protocol instead.