Here's the Android release notes: http://developer.android.com/about/versions/kitkat.html Highlights: * WebView is now based on Chromium * KSM and zRAM integrated into stock kernel * Public SMS framework * Printing framework * Storage access framework
This sounds remarkably similar to the M7. This functionality of Android 4.4 requires hardware support, which initially is only provided by the Nexus 5. It allows for continuous sensor measurements, only waking the application processor when it delivers a batch of them.