One feature that has been missing from the Google App for some time has been home screen rotation. It is something very basic, but has been left out. When Android Marshmallow was in the Developer Preview stage, both Preview 1 and 2 allowed for the home screen to be rotated, but it was axed in Preview 3. The good news is that the latest Google App update (18.104.22.168) brings back home screen rotation.
In order to enable this feature, you have to open up the Google App, or swipe over to your Google Now page. Once there, swipe out from the left and open up the settings. Right on the first page of the settings their is a Home screen tab, and there is a toggle to ‘allow rotation’. This is something that has been missing on the Google Launcher.
The landscape screen has a slightly different layout than the portrait screen. The prevalent Google search bar that is usually placed at the top of the screen has been replaced by the more subtle Google ‘G’ logo and a microphone. I kind of like the more subtle approach with the microphone and ‘G’ off to the side as it opens up the wallpaper. Not only that, but the app icons appear smaller than when in portrait.
Below you can see Google Now and the app drawer in landscape mode. Google Now is still the same proportion when rotated. The app drawer in the landscape mode has a grid size of 5×3 versus the portrait grid size of 4×6. They did a good job of leaving some open space to not make it look too cluttered.