KitKat, the most recent version of Android, brings features as sweet as its namesake to the new Google Nexus 5. Among these, you'll find a new phone dialer, Caller ID, true full screen, a new Hangouts app, and printing abilities.
To use all of these new features, KitKat also has an updated Google Keyboard. This keyboard is very similar to the version released on the Google Play Store, except the swiping line color has changed, you can glide over space to insert it between words, and some upgraded emoji are included.
Disclaimer: Installing third-party software means taking risks with your device and/or personal information. You will be responsible for any issues caused by the installation, and should only proceed if you are prepared to deal with the resulting consequences.
First, you'll need to make sure you have the ability to install software from outside the Google Play Store. Open your Settings menu, go to Security, and then check the box next to Unknown Sources.
Next, download the actual Google Keyboard APK (Android Package). You can download it directly to your device, or you can download it to your computer and then transfer it to your device's storage later (via USB, cloud storage, or another preferred method of transfer).
Here are the mirrors shared by Android Police:
Now you're ready to install the keyboard on your device. If everything is set, you should be able to tap on your completed download (or the file you moved to your device) and the package installer will pop up to finish the process. However, on some devices (such as the Note 2), you may only see a prompt to use programs that have nothing to do with installing apps. If you are running into this issue, you can easily work around it by uploading the app to your Dropbox or Google Drive account and installing from there.
Unlike some other keyboards, Google has included an setup tutorial. After the install completes, press the open button and you'll be walked through setup. If you skip this by mistake, you can easily navigate through Menu > Language, and input to enable the keyboard and adjust settings (like vibrate or sound on keypress), too.
Finally, open any app where you can type to test it out. The emoji have their own button in the bottom right-hand corner, but if you don't see it in some apps, try long-pressing Enter or Search. Please note that emoji will show as black and white versions only if you are not on Android 4.4.
What do you think of the new version? Is it faster? More intuitive? Share your experience with Google Keyboard 2.0 in the comments.