Android L brings a major design overhaul to the world’s most popular mobile operating system, and included in that design overhaul is a new look for Google’s keyboard app. It’s more colorful, flatter, and just looks more modern than before, and thanks to the tinkerers and bright minds over at the XDA community, you can now install the new Google Keyboard on any device running Android KitKat.
Developer bejunk has created a package which contains the APK file and all the related library files. Once the keyboard is installed, users can switch to the new Material theme (part of the Material Design philosophy Google is quoting for Android L) from the Advanced settings » Color scheme menu in the keyboard settings. Unfortunately, a rooted device with a custom recovery is needed to flash the keyboard package, but if your device meet those requirements, you can simply head over to the source link and download the necessary files.