Since Android L is in a very early beta, and the average user can't nor is advised to install it manually, the otherwise attractive keyboard was, at first, seemingly reserved for root users, who could snatch the .apk off xda-developers and simply install it on their rooted device. Thankfully, however, a certain developer made the L keyboard available as a third-party app on the Google Play Store, allowing even non-rooted handsets the privilege of messing around with it. Unfortunately, if you haven't taken advantage of this opportunity yet, you might be out of luck.