What has differentiated modern consoles from the previous generations? Sure, there are better graphics and more creative uses of hardware, but that's not all. One of the biggest changes to the current gen was the introduction of system-wide Achievements/Trophies, online leaderboards, and more social interactivity.
Google doesn't want the Play Store to be left behind and has today introduced many of these features for the mobile crowd. In fact, Google Play now has a games offshoot. Achievements, leaderboards, online play, and even cloud game saves are all a part of this transition. According to Google, these items are available to Android users but also for many iOS products.
Things like leaderboards can be checked through the application itself or on Google+. Gamers can also situate themselves for a multiplayer game through use of G+ Circles. Of course, how many will actually do that is unknown, but the feature exists all the same. Despite the launch, it will take time for a majority of developers to make use of the new services.