From Xojo Documentation
| This class is only available on platform.
For cross-platform compatibility, use ＃If...＃Endif with the Target... specifiers to make sure you will not attempt to use this class on an incompatible platform.
New in 2021r1
Allows the user to authenticate either with FaceID or TouchID.
|To use this class you must turn on the User Authentication switch by selecting iOS in the Build Settings of the Navigator and then clicking the Advanced tab in the Inspector.|
When an application or a particular function of an application should be used only by the authorized user of the device, the UserAuthentication class can be used to ensure this. By requiring the user to authenticate, the device's operating system takes responsibility for this. Calling the Request method will begin the process. If it's successful, the AuthenticationSucceeded event will fire. If it fails, the Error event will fire. Keep in mind that this is an asynchronous process.
iOS Projects on iOS and iPadOS operating systems.