From iOS 18, you can change the Torch and Camera shortcuts on the lock screen to perform other functions.
One available function is to open an app of your choosing.
When you attempt to do this however, you get locked in the dialog box where you choose the app.
Enable VoiceOver.
Go to the lock screen and enter Edit mode. Select the option to Customise.
Select one of the shortcut buttons at the bottom, which by default are Torch and Camera.
Select the option to Open App.
Select the button to Choose an app and select the app you want from the list.
You are now trapped in the dialog box and cannot exit out unless you use the Two-Finger Scrub gesture.
Use the Two-Finger Scrub gesture to exit the dialog box.