There are seven packages in the Google VR Java API, six as part of the SDK and one as part of the NDK.
com.google.vr.sdk.base Code for the core Google VR API.
com.google.vr.sdk.audio Code for 3D-spatialized sound.
com.google.vr.sdk.controller Code for using the Daydream controller with your VR app.
com.google.vr.sdk.widgets.common Shared code for embedding VR view content.
com.google.vr.sdk.widgets.pano Code for the VR view Panorama Widget.
com.google.vr.sdk.widgets.video Code for the VR view Video Widget.