It's a fourfold difference (~2200ms versus ~9100ms on three runs of each) on synthetic benchmarks (Sunspider 0.9.1 on an iPhone 4S running iOS 5.1.1, UIWebView was tested through Instapaper 4.2), which I would call significantly worse.
> otherwise nobody would use it.
Performance is not everything: they are convenient especially given iOS's debatable story for switching between applications (especially back and forth between an application and a web browser).
> But lots of apps do use it e.g. Linkedin, Facebook, Reeder, Google Search, iCab Mobile etc and it is not noticeably worse.
It's "not noticeable"[0] for JS-light websites because... well the JIT is for javascript code, running JS slower doesn't matter if there's no JS code.
[0] it is most definitely noticeable, many sites — especially full-page non-mobile ones with ads shit — load significantly faster using Safari than using embedded UIWebView.
It's a fourfold difference (~2200ms versus ~9100ms on three runs of each) on synthetic benchmarks (Sunspider 0.9.1 on an iPhone 4S running iOS 5.1.1, UIWebView was tested through Instapaper 4.2), which I would call significantly worse.
> otherwise nobody would use it.
Performance is not everything: they are convenient especially given iOS's debatable story for switching between applications (especially back and forth between an application and a web browser).
> But lots of apps do use it e.g. Linkedin, Facebook, Reeder, Google Search, iCab Mobile etc and it is not noticeably worse.
It's "not noticeable"[0] for JS-light websites because... well the JIT is for javascript code, running JS slower doesn't matter if there's no JS code.
[0] it is most definitely noticeable, many sites — especially full-page non-mobile ones with ads shit — load significantly faster using Safari than using embedded UIWebView.