The rules explicitly forbid any HTML renderer or JS interpreter aside from WebKit, JIT or no JIT. I believe all the popular third party browsers today still use the non-JIT UIWebView rather than WKWebView because the former gives you more control over the request cycle
WKWebView has JIT. In executes the JS in a different process than the hosted app; there the JIT lives, this special process is whitelisted to do JIT magic.
I understand that, the original OP was stating that none of the "browser skins" had JIT because they all used UIWebView, which isn't the case with the link I posted :p.
