Improved software and Nexus 5’s new hardware mean Android responds to your touch faster and more accurately than ever before.*
Just say “Ok Google”
You don’t need to touch the screen to get things done. When on your home screen* or in Google Now, just say “Ok Google” to launch voice search, send a text, get directions or even play a song
*Currently only available on Nexus 5"
Por que não para o Nexus 4? O Google tem que dar uma explicação, não?