Just in time for Halloween, Google has given us a new candy mobile operating system treat: Android 4.4: KitKat . Here's what you need to know about it now.

Image: Google

1. KitKat's not widely available yet

KitKat comes on the just-released Nexus 5 . If you want to use it today on an older smartphone or tablet, you're out of luck.

Google promises that it will soon be available on the Nexus 4, 7, and 10, the Samsung Galaxy S4, and the HTC One Google Play edition in the coming weeks as an over-the-air (OTA) update. If you're running a Nexus device, you'll also be able to flash the new Android's image to your tablet or smartphone. At this time, the evening of October 31, the KitKat images aren't available. However, if you're an Android developer, KitKat source code is available now.

If you're not a programmer, or you don't have one of the supported devices, technically speaking, you should still be able to run KitKat on many older devices. That's because Android 4.4 can run on devices with as little as 512MB of RAM.

Whether you really will be able to easily get the update for your gear is a question that depends on your carrier and your phone manufacturer. If your device is older than 18 months, I wouldn't count on ever getting Android 4.4. If that's you, your only hope is for CyanogenMod or another Android porter to bring the firmware to older devices.

2. Google Now integrated even deeper into KitKat

With Google Now , Google uses all it knows about you, which is a lot , and makes it even more a part of the Android experience. According to Google, all you have to do is say "'OK, Google' to launch voice search, send a text, get directions, or even play a song you want to hear". Android 4.4 is a big step forward towards making devices that are not merely touch activated, but also voice activated. We can see the future of both Google Glass and smart watches from here.

3. Improved phone app

I know how 20th century of me it is to want to use a smartphone as a phone, but darn it, sometime I do, and Android 4.4 makes it easier. Google is "making calling easier than ever, by helping you search across your contacts, nearby places, or even Google Apps accounts (like your company’s directory), directly from within the app".

In a related development, Google+ Hangouts, which is also more closely tied into KitKat and replaces Google Talk, includes texting, location sharing, and animated GIFs. This functionality will be available in any device running Android 4.x or higher. Eventually, Google Voice, Google's voice-over-internet-protocol (VoIP) service, will work with this, but for now, Google Voice and new Hangouts are having trouble cooperating with each other.

4. Better memory management

Google did more than just reduce Android's 4.x's memory footprint. "KitKat streamlines every major component to reduce memory use and introduces new APIs and tools to help you create innovative, responsive, memory-efficient applications."

This more efficient use of memory will show to its best advantage as KitKat starts to catch on and developers start building apps that can take full advantage of it. For users, this will mean your applications will run faster, and switching from one program to another will go faster.

5. Quickoffice integration

First, Google bought Quickoffice, an Android-based office suite. Then, Google made Quickoffice free . Now, Android 4.4 will come with Quickoffice pre-installed.

With the latest Quickoffice, you can create and edit Word, Excel, and PowerPoint files; access files in Google Drive and on your device; open and view PDF files; and attach files to emails. Does it sound to you like Google is targeting Microsoft Office on tablets? It sure does to me.

Android 4.4 has many other noteworthy features — better printer support, smart caller ID, support for multiple local and cloud storage services, and, at long last, native screen recording — but you get the idea. While Android 4.4 isn't a revolutionary update, it's certainly one that's filled with goodies. Now, if you'll excuse me, I'm going to compile the source code and flash my Nexus 7 with it.

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