Secret Messages File
How or what do I need to get a secret messaging file on my IPhone? My friend has one. It shows up in her settings but she’s got an IPHONE 7. I have the SE. Is that why? Is it a download?
iPhone SE
There are apps (not by Apple) in the App Store, where one can hide messages. Go to App Store and see if a message hiding app will provide what you're looking for.