iPhone 6 simulator check results:
* Layout is mostly ok, except the status bar in landscape mode seems overlarge (?)
iPhone 6 Plus simulator check results:
* Layout roughly same as 6; looks good except that large status bar in landscape
* Web content appears to be rendered at 2x resolution and scaled up; it appears slightly blurry in the simulator compared to text drawn directly on native buttons and labels.
It's possible that this is a limitation of UIWebView; there's a new WebKit wrapper interface available on iOS 8 which may be more featureful...
Actually in both cases, the web view reports itself as having a width of 320px and a devicePixelRatio of 2 (matching the 'classic' iPhone width). Might have to do something to opt in to the new native sizes. Sigh.