Don’t let the version number trick you, Android 4.4 KitKat isn’t a minor release. This isn’t a small update like Android 4.3, but a big new release with lots of important features.
Google’s changed the way Android looks, created their own new launcher, made the dialer much smarter, further consolidated their messaging services, given the Email app love, and added many new features for app developers to take advantage of.
Google Experience Launcher
The Google Experience Launcher may not technically be part of Android 4.4, but it debuted along with Android 4.4 on the Nexus 5. On Android 4.4, the Google Experience launcher has a partially transparent status bar and navigation bar on the home screen, showing off your wallpaper and hiding those black bars.
You can easily install the Google Experience Launcher on any Android device running Android 4.1 or later. Google is currently only officially offering the Google Experience Launcher on the Nexus 5, so you’ll have to activate it yourself on other devices — even other Nexus devices, like the Nexus 4 and Nexus 7.
Android 4.4′s new dialer also allows you to search for businesses and dial their phone numbers — right from the dialer. For example, you can open the dialer, search for “pizza,” and quickly call a nearby pizza place.
Whenever you get a phone call, Android can now query Google’s servers to provide caller ID information for you. This feature is enabled by default, but you can disable it if you like. The dialer is now powered by Google search.
Blue is Out, Gray is In
The most immediately noticeable change is the shift from the Tron-like neon blue of Android’s Holo interface to a new, neutral gray color. The battery, Wi-Fi, and cellular icons on Android’s status bar, for example, are now gray. The options in the quick settings panel are also gray, as are the accents on the official Google Keyboard.
In theory, this will provide a more neutral canvas for app developers. For example, Netflix’s red app will look better with gray system icons than blue ones.
Hangouts SMS Integration
Google’s Hangouts app — the replacement for Google Talk – now has integrated SMS support, eliminating the need for the separate Messaging app. This feature also isn’t exclusive to Android 4.4, but is also available on older versions of Android along with a recent update to Hangouts.
On Android 4.4, Hangouts registers itself as a “SMS provider.” Any other SMS app can also choose to register itself as an SMS provider, becoming the default messaging app. Any app can listen for incoming SMS messages, but only a single app — the user’s default SMS app — can send SMS messages.
Android now includes a printing framework. It’s a built-in system feature that supports both Google Cloud Print and HP ePrint by default, but developers can add support for new types of printers using the API. This means you should be able to install support for other printers via an app from Google Play and they’ll integrate with Android’s printing system.
You’ll find a new Printing option on Android’s Settings screen, and many built-in apps support printing. For example, you can tap the menu button in Chrome and tap the Print option in the menu to print a web page.
KitKat includes a new way to browse for and pick files. This file picker supports both local, on-device storage and cloud storage services like Google Drive. However, any cloud storage service can integrate with it. Support for Box is already offered, while other cloud storage services like Dropbox or SkyDrive could implement a “document provider” and appear in this list. Whenever you use the file picker, you’ll be able to choose a file from any local source or cloud storage service.
Android now also offers an “immersive mode” feature that allows apps to hide the status bar at the top of the screen and the on-screen buttons at the bottom of the screen on Nexus devices. This means that apps like games, video players, and eBook readers could use the entire screen for content. This won’t happen automatically; it’s up to app developers to choose whether this is right for their app.
To go along with this, Android includes two new edge gestures. When immersive mode is enabled in an app, a swipe from the top or bottom edges will reveal the hidden status bar and navigation bar.
Email App Improvements
The included Email app has finally seen some love. The Mail app now looks almost like the Gmail app and shares many of the same navigation features and settings. It no longer feels like a forgotten relic.
Tap and Pay
KitKat includes a “Tap & pay” option on the Settings screen. Thanks to “host card emulation,” any app on Android can now emulate an NFC smart card. In the near term, this means that any device with NFC should be able to use the Google Wallet app. In the long term, this means that there’s an integrated way for various apps — such as loyalty card apps and competing digital wallets — to work with NFC point-of-sale terminals.
Android now also allows apps to use “Reader Mode” and function as NFC readers.
Decreased Memory Usage
This isn’t a great feature for showing off in screenshots, but the most significant change in KitKat is the amount of optimization that’s gone on. Android KitKat can now work on devices with as little as 512MB of RAM. This means Android should perform much better on low-end devices and any manufacturers still using Android 2.3 Gingerbread on their cheapest devices should finally be able to upgrade. On higher-end devices where it already performs well, Android should perform even better.
There’s a new Process stats option on the hidden Developer Options screen that displays more information about each running process and its memory use. This should give developers more information they can use to optimize their apps’ memory use.
Google’s Android KitKit page for developers lists many more features. Many of them are intended for developers — that’s because developers will need to integrate these features into their apps for them to actually be useful for the rest of us.