https://techcrunch.com/2018/03/07/heres-the-first-developer-preview-of-android-p/

Just like in the last two years, Google is using the beginning of March to launch the first developer preview of the next version of Android. Android P, as it’s currently called, is still very much a work in progress and Google isn’t releasing it into its public Android beta channel for over-the-air updates just yet. That’ll come later. Developers, however, can now download all the necessary bits to work with the new features and test their existing apps to make sure they are compatible.

As with Google’s previous early releases, we’re mostly talking about under-the-hood updates here. Google isn’t talking about any of the more user-facing design changes in Android P just yet. The new features Google is talking about, though, will definitely make it easier for developers to create interesting new apps for modern Android devices.