Users of Kit Kat might be wondering what all the Google Voice fuss is about - you say "Ok Google" and your phone/tablet does nothing, so it seems not to work. The problem is that it DOES work, but only if you use (simplified) US English. Google uses separate settings for text input and voice search, so the fix is to go to:
Settings>Language & Input>Voice Search>Language>English>select US English.
Now try saying "Ok Google". Surprised? Now that you have simplified English for Kit Kat it works! :thumbsup:
Ok Google now launched in beta for your desktop as a Chrome extension.
https://chrome.google.com/webstore/detail/google-voice-search-hotwo/bepbmhgboaologfdajaanbcjmnhjmhfn/details