This looks to be little more than another PDF-type viewer similar in function to Zinio only without much in the way of features. It seems to be about as capable as the Google Play magazines Android app and I have to wonder why anyone would want to use it.
This isn't just me not getting it; there actually are other apps which do a better job.
I might avoid magazines because they don't offer enough information packed into small enough containers, but that doesn't mean I don't understand them. Their goal is to entertain more than inform, Every little detail from the page layout to the size and placement of photos and even the behavior of the app needs to support that goal.
This goal of entertainment is why so many comics apps have a directed viewing mode now, and it is also why some magazine apps (B&N's, for example) add subtle tricks like a faux page turn. They are intended to add to the enjoyment of the reading experience.
The reading experience with Google's Magazine app is at best utilitarian in comparison. Maybe they will improve it over time, but right now there are better options.