Google announced today that it is rolling out changes to Google Play, in which it will better differentiate between apps that are designed for tablets and apps that are designed for phones.
Regardless of whether or not you developed your app for one specific type of device or the other, Google will determine your app's label based on if it meets the criteria for being "designed for tablets". Essentially, if it does not, it will automatically be labeled "designed for phones".
Google announced that the changes were coming a while back, but now they're going live.
Users who are browsing Google Play from a tablet will see the "Designed for Tablets" section as the default view from top lists, though they can still switch views to see all apps and games.
"Every day thousands of Android developers are taking advantage of the tremendous Android tablet opportunity," Google said in a Google+ post. "The flood of new users coupled with the increased screen size means new user experiences, more engagement, and more monetization opportunities for your app."
You can see if your app meets the tablet criteria in the Developer Console. It will list any issues that need to be addressed. Here's a tablet quality checklist.