If you liked the Nexus 5 launcher, you can now have it on your android device running Android 4.4 KitKat.

Google Now Launcher Features:

• Just say "Ok Google" - when you're on your home screen, just say "Ok Google" to trigger voice input. Then say your search query. Or tell your phone what to do, like send a text message, get directions, or play a song (available in the US, UK, and Canada).
• Faster search - tap the search box and you can enter your query immediately.
• Easy access to your favorite Google products and services, like Gmail, YouTube, and Maps.
• Larger viewing area - the status and navigation bars are now translucent, so your wallpaper pops from every pixel, and is even visible when you expand your apps drawer (when supported by device).
• Intuitive wallpaper picker - select any image that's stored on your device, or in the cloud. Position and preview your wallpaper before you set it.