From Xojo Documentation
| This item was deprecated in version 2020r2.
Please use MobileContainer as a replacement.
| This class is supported on Mobile (iOS).
Use ＃If...＃Endif with the Target... constants to ensure you only use this class where it is supported.
An iOSContainerControl is a way to create a group of controls that are treated as a single control. It is a great way to simplify complex view layouts. In addition, with iOSContainerControl, you can create reusable controls to include on multiple views or even other iOSContainerControls.