From Xojo Documentation
| 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.
A pre-existing image that was either added to the project or is loaded from another source.
An iOSImage is immutable, which means that it cannot be changed. Because of this it can be cached by iOS for speed. If you need to change an image, you should instead create it as an iOSBitmap.