Its WebView on Cocoa. UI Classes belong to the iOS Framework. https://developer.apple.com/library/...Reference.html
Still you are right. A WebView will probably yield better results.
Katie, do you have by chance a tip how to get the keyboard working in the client?
What bewilders me. The client uses a different key combination to past text than the OS itself. Leave me with a bad feeling that the OS is not involved here.