How to downgrade from ionic 4 (beta) to ionic 3 (latest stable)


I’ve developed an application with Ionic 4.0.0-beta.13. But its not working (Showing blank screen) on devices with android version lower than 7.1.1.
This is due to the below running known issue
So i wan’t to downgrade my Ionic version to latest stable version.
Can someone please help me on how and what changes it needs?