A new design element was found several weeks ago in the Google Play Store that violated Google's own Material Design guidelines. A nested navigation bar is suddenly appearing under a main tab of categories. As an example in the picture above, you can see Pop, Alternative, Rock, etc. under the main categories, Genre, Artist, Album, etc. Google has specifically said in the past, “Tabs should not be nested.” A wider rollout of this change is happening today.
Categories were split into their own high-level tabs a few weeks ago, with a navigation bar now appearing under those tabs that provides links to different sections. The new icons are more user friendly and Google is hoping they'll encourage users to explore more of the Play Store's content. In addition, the new navigation bar is persistent and doesn't disappear as you click through. The old design is below.
And here's the new design. A new “For You” chip also appears under the Home tab and suggests apps that Google thinks will be of interest.
This persistent nested tab design violates Google's original Material Design guidelines, although the design is clean and easy to navigate through. The changes are relatively small and aren't redesigning the wheel, but it's interesting how Google is breaking its own rules by implementing these upgrades.
Source: 9to5Google
