Android L's heads up notifications feature arrives early through third-party app

When Google's Android L operating system arrives later this year, it'll bring a new heads up notification tool that will alert users to incoming calls and alerts without disrupting their current activity.
Unfortunately, Android L won't be available until this autumn, but users will have the chance to download a version of the functionality, thanks to a third-party app available on the Google Playstore now.
The Heads Up! application from developer Alexander Breen works on devices running Android 4.3 and above brings those floating, overlaid notifications.
All users have to do is enable third party apps in the Android settings and choose which applications they would like to receive heads-up notifications from.

Enabler

The process is a little complicated, but Lifehacker has a useful guide on how to enable the app as your chief means of receiving notifications.
You can also check it out in the video below.