I have built lots and lots of stuff on mobile web. Never once was JavaScript perf the bottleneck on iOS. Never (especially since the rise of retina screens).
I think there is a lot of hyperbole around the whole JIT in webview thing from people who don't have a good grasp of where the performance problems are on mobile web.
I think there is a lot of hyperbole around the whole JIT in webview thing from people who don't have a good grasp of where the performance problems are on mobile web.