Can I allow more than one app in "Single App Mode"? If I use "Apple Configurator 2" to lock an iOS device, can I allow two or three or four specific apps ?

Or is it really, literally, "single" app mode and only a single app can be allowed ?

Thank you.
No, you can't allow more than one app in "Single App Mode"

Apple also states


  Single App Mode forces the selected app to open on the supervised
  device and prevents the use of other apps. When this payload is
  active, the app reopens immediately after the device is restarted.