I am developing a companion app in SwiftUI for an existing iOS app. When setting WKSupportsAlwaysOnDisplay to NO in info.plist on the simulator and three different watches, animations start to lag: both in system components (like Picker) and custom ones.
When WKSupportsAlwaysOnDisplay is set to YES and the user disables Always On mode support on the watch in system settings, there are no such animation issues.
Deployment Target is installed on watchOS 9. The app supports Workout Processing and Audio background modes.