I have a simple WKWebView browser in my app. I happened to test it on an iOS 9.1 phone with parental controls turned on in - Settings - General - Restrictions. In testing (honest) I happened to click a link to an adult site. I saw
You cannot browse this page at [URL] because it is restricted.
I wasn't aware that WKWebView implemented Apple parental controls. It's handy if it does, avoiding age restriction problems in the store. Is what I have seen the parental control operating? Is there an Apple document somewhere that says that WKWebView implements parental controls?
I had to both turn on Settings - General - Restrictions and also set Websites - Limit Adult Content to see this behaviour. When I did that, I also saw this behaviour on an iOS 9.2 iPad.