Brief Intro: Appium is a well known Open Source Automation Framework for automating Mobile Native, Hybrid and Web applications across platforms(Android, iOS, Windows and Firefox OS).
Brief Intro to what this new driver intended and architecture details can be found here
We highly encourage you to run your existing stable appium android scripts against this new driver and report the bugs if you come across any at https://github.com/appium/appium-uiautomator2-driver.
From your desired capability it is requested by specifying the desired capability automationName as uiautomator2 when starting a session.
Prerequisites: This module should support for Android API Level 20(5.0) and above