Slow carriers updates of android are pushing google to update browser independent of carriers, and developers to move to the browser as a universal platform.
Ars Technica
Fragmentation remains an issue for third-party Android application developers. The wide spread and slow rate of adoption for new versions of the operating system prevent developers from being able to use the latest APIs. But native application developers aren't the only ones who are feeling the pain. A prominent Web developer has recently drawn attention to the challenges that Android version fragmentation poses for mobile Web development.
As we explained in some of our recent Android browser coverage, the platform's default Web browser has historically not been very good at handling the most intensive application-like Web experiences. It lacks support for many modern Web standards and has difficulty handling things like animated transitions. Google is finally correcting the problem by bringing a full port of its excellent Chrome Web browser to the Android platform.