Android Kitkat (for nexus 5 only..currently well not all for sure)

Beautiful & Immersive

A more polished design, improved performance, and new features.

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.

A work of art

While listening to music on your device, or while projecting movies to Chromecast, you’ll see beautiful full-screen album and movie art when your device is locked. You can play, pause, or seek to a specific moment.

Immerse yourself

The book you're reading, the game you're playing, or the movie you're watching — now all of these take center stage with the new immersive mode, which automatically hides everything except what you really want to see. Just swipe the edge of the screen to bring back your status bar and navigation buttons.

Faster multitasking

Android 4.4 takes system performance to an all-time high by optimizing memory and improving your touchscreen so that it responds faster and more accurately than ever before. This means that you can listen to music while browsing the web, or race down the highway with the latest hit game, all without a hitch.

Smart & Simple

Google smarts improve every corner of the Android experience.

The future is calling

The new phone app automatically prioritizes your contacts based on the people you talk to the most. You can also search for nearby places and businesses, your contacts, or people in your Google Apps domain.

A smarter caller ID

Whenever you get a call from a phone number not in your contacts, your phone will look for matches from businesses with a local listing on Google Maps.

All your messages in the same place

Never miss a message, no matter how your friend sends it. With the new Hangouts app, all of your SMS and MMS messages are together in the same app, alongside your other conversations and video calls. And with the new Hangouts, you can even share your location and send animated GIFs.

Emoji everywhere

Sometimes words can’t express how you feel. For that, there’s Emoji, the colorful Japanese characters, now available on Google Keyboard.

Grab & Go

New features help you get things done while you’re on the move.

Print wherever, whenever

Now you can print photos, documents, and web pages from your phone or tablet. You can print to any printer connected to Google Cloud Print, to HP ePrint printers, and to other printers that have apps in the Google Play Store.

Pick a file, any file

From apps like Quickoffice, you can open and save files on Google Drive, other cloud storage services, or your device. And with quick access to recently used files, it's easier than ever to send the file you were just working on.

Your office, anywhere

Create and edit documents, spreadsheets and presentations from your phone or tablet with the newly redesigned Quickoffice