WebGL is now enabled: Until now, WebGL was a hidden feature in iOS 7 that could not be enabled by the developer. But starting in iOS 8, WebGL is now officially supported in both WKWebView and UIWebView. This is huge for developers who require native-level 3D animation capability, especially for game app developers.
IndexedDB is now supported: IndexedDB is a persistent database engine for managing structured data with transaction support. It allows a more advanced query engine and a sophisticated API set. Now that IndexedDB is supported, managing huge amounts of data has gotten much easier.
CSS3 support-level test: We also wanted to check for any improvements to CSS3 capabilities. We did this by running the CSS3Test.com benchmark suite.
There seems to be no difference in CSS3 support level between WKWebView and UIWebView. However, iOS 8 has implemented many more CSS3 features than iOS 7. Here are some of the new features we have confirmed and are now available in iOS 8:
And Apple notes that the subpixel rendering is now on by default, which means all apps will get a clearer and crisper look. In some situations, the rendering result may be different. It is suggested to check all pages if they have any corrupted design.