It's not long before apps from the latest version of Android are ported to all other versions of Android. Some require root and some don't. But, here in the case of Android L Keyboard you can just make it work in your device without root.
Xda senior member, asdfzz, has modded the app, and now it may just work on any device. I tested it on Lg pro lite dual and it worked. Someone has tested it on Moto G running 4.4.2 without root and it worked there.
You can find the original source of the thread here: link
Installation:
- uninstall the google keyboard if you installed it from play store before.
- Just install the apk provided below like any app installation. It is simple as that.
- after installing you have to do one more thing. Change the color scheme( You have to go to Google Keyboard settings, then Advanced Settings, and lastly change
the "Color scheme" to "Material" .
As the source says, phones such as Stock Nexus without root may have problems with this app as it already has got google installed keyboard as system app.
But for those you may need to delete the system app file and install.
For rooted phone check this link for another tutorial to install on rooted phones : LINK